Thursday, 5 July 2018

Henry Justice Ford Project - The Trees That Bleed

Armour class: As Leather.
Hit dice: 2
Move: Rooted to the spot.
Attacks: Branches (d6) and roots (d4)
No. Appearing: 3d8

Morale: 12
Treasure: 50 GP per tree.

Alignment: Neutral


Trees That Bleed are a perversion of the natural order in which plants are inanimate and don't resist the depredations of the animal kingdom. These trees seem, at first glance, to be much like any other. Their only distinguishing feature visually is that, instead of sap, thick red blood flows through their woody veins.A careful observer can spot scabs of congealed blood on the tree's bark.

They are found growing in dense copses, each tree within reach of several of its peers. For the most part, the trees are dormant. They remain inanimate, content to simply grow and photosynthesize. Only when one of their number is threatened - perhaps by woodcutters or dangerous beasts - do they stir into motion. At this point, the whole grove goes berserk, lashing at intruders with branches and roots.


An encounter with Trees That Bleed is all about positioning. By the time the trees animate, the PCs are probably in their midst. Draw a map of the grove, put the PCs somewhere in the middle. Each tree ought to be within 10 feet of one or more of its peers. Each tree has 15 feet reach with its branches and 5 feet with its roots. With the large numbers of trees present, the skill in the fight is to find points where fewer trees can reach you: the gaps and clearings. 

As plants, Trees That Bleed are affected by spells like 'command plants' and 'talk to plants' but not by spells like 'hold monster'. Their tough, woody nature means that they take a maximum of 1 damage from everything except Axes & Fire. 

Turn Sequence in The Dolorous Stroke


I've been thinking about how the turn procedure and activations work in my wargame. I initially had a setup very much like GW's LotR game: roll for inits, player 1 moves, player 2 moves, player 1 does actions, player 2 does actions, resolve fights.
It was... okay, I guess.

But I've moved away from that. I dare say what I came up with isn't massively revolutionary, but it's working nicely for what I have in mind.

The turn starts with a roll for inits. After that, players alternate acting with their models until everybody has done something, and then a new turn begins.
When you activate a model it gets to do one thing. It can move, or shoot, or fight, or cast spells, or whatever. But each turn it gets one action. So, if you use your action to charge into combat, you don't resolve the fight on the same action.
Any model in base-to-base contact with the enemy is locked in combat. When it activates, it must use its action to resolve the fight: both sides roll off, the winning side strikes blows against the losing side, and the fighters are seperated (meaning they're then no longer locked in combat). 

What this means is that charging is good because you get to control the tempo of the game with it: you force your opponent's model to use their action to resolve the fight (which could go either way). Effectively, you lock them out of doing anything but fight for the turn, whilst the charging model still gets their charge move. 
Since you don't have to activate a model locked in combat immediately, you can charge more of your own models in to try to get a numerical advantage. Or you can activate early and resolve the fight 1-on-1 to prevent your opponent from ganging up on you. 
It makes the order you activate stuff in become critically important. Activating the right stuff in the right sequence becomes how you control the action-economy, and controlling tempo and so on is a thing I want to be a focus of the game.

To reinforce this, I'm putting a few options in that are explicitly tempo-based mechanics. 
Every model has a 'delay' action available to them. You do nothing for your action, but if you pass a Wits roll, you get to make a second activation. You can only delay once per turn, or it gets silly. Effectively it gives you a chance to wait and see what your opponent is doing before actually acting, letting you slow down in the normal pattern of alternating.
There's a fighting style (Hold the Line!) that characters can learn that lets them Delay even if locked in combat. Basically, it lets a character locked in combat delay to keep their enemies pinned in place without resolving the fight and thus seperating the combatants.
Duels and Jousts also mess with the normal action economy: in a duel, you don't separate the fighters after resolving the fight. They stay locked in combat until one side wins. Both sides need to agree to the duel, but when they do you're efectively putting two models out of the running for several turns as they only focus on each other. Jousts are kinda the opposite of this: after resolving a joust both sides get a free move as they hurtle past each other. So, jousting becomes a way to get disproportionate mobility whilst also getting hits in against your enemy.
I've put in a few skills that directly fuck with the alternating action sequence. Leader lets you chain activate: after you activate the leader, you can immediately activate somebody under their command before your opponent gets to respond. Follower is the inverse of this: after activating a model, you can immediately activate a follower. Both of these let you get a burst of two actions (or three if you go leader-normal-follower in sequence) without your opponent getting to react. You don't get to do more stuff but, again, I've found it gives players ways to control the tempo.

One thing that was mentioned in response to my post about fiddling with gender-roles is that it makes sense for noblewomen in the game to have more of a behind-the-lines leadership role. Giving them a lot of the tempo-control tools seems like a good way to realise this. Similarly, giving peasant characters abilities that make their interaction with tempo reactive means that they'll always be following the lead set by the knights, which feels right.

Wednesday, 4 July 2018

Gender in the Dolorous Stroke

I've been thinking about the role of women in the world I'm slowly building up for my Arthurian-inspired skirmish game. As False Patrick talks about in this post, gender roles are rather strong in the chivalric romances I'm taking inspiration from. Courtly love, questing to win the favor of a particular lady, damsels needing rescuing and so on are central to most of these stories. On the other hand, I'm a bit of a lefty, and I like playing chicks in the games I'm in, and this is a skirmish wargame about knights fighting each other. The normal roles of women in these tales would keep them from the battlefield. So, if I'm to find a place for women in the setting beyond 'the object of the main characters' quest', what should it be?
Right away, I rejected the idea that we just make the setting gender-blind. I've seen this done well; for example, the larp Empire has the nation of dawn, which are strongly Arthurian inspired and feature a lot of themes of courtly love and so forth, in a setting which doesn't distinguish along gender lines. However, I wanted to stick to the narratives seen in the stories I was emulating more closely.
In the end, I decided to flip the assumed power structure in the setting, making things essentially matriarchal. Essentially, the business of leadership is seen as a woman's task; the setting is ruled by queens and princesses rather than kings and princes. Men (at least as far as the nobility are concerned), are essentially subservient to female rulers. Their place is to serve a queen or other (female) liege. 
Of course, with women in all the positions of political power, the status of noblemen depends entirely on their queen's favor. This, naturally, leads to men jostling to attract the affection of their rulers. Which, in turn, leads to the quests for a lady's favor that make up so much of the canon of chivalric romances.

This, of course, contrasts with the ideas of knightly orders as a more exclusively male arena. Like with many esoteric societies (medieval mason's guilds, the cult of mithras, etc) there's probably quite a strong gay undercurrent here. Probably nothing worth going into in much depth, but in the same way that IRL the Navy has a reputation for being the gayest of the armed services...
Interestingly, in the historical medieval period, there was actually a similar phenomenon with monasteries and nunneries. People for whom normal marriage wasn't at all appealing often got out of it by joining a cloistered community, so the number of gay individuals in cloisters seems likely to be quite high. Indeed, the catholic church even had particular recognitions for pairs of male monks with 'a particularly strong brotherly love for one another'. Whilst not recognised as gay in the sense a modern audience might, the parallels are clearly there. But I digress.

I'm also writing the setting so that breaking expected gender roles is more possible than it was historically. A nobleman who's driven to rule as a seneschal can do that, it will just be seen as effeminate and out of place. Providing he's good at the job, though, nobody's going to stop him. Likewise, women who want to take up armour and become knights can do that, they just open themselves up to all sorts of scandalous gossip. At least a few of the example PCs I'm writing up subvert the expectations of their sex in this way.

So yeah. That's where my thoughts are on the matter. 
Incidentally, anybody who starts shitting up the comments by shouting about the culture wars/SJWs/pol/whatever is getting blocked and deleted. This is far more about creating the atmosphere I want for the game than any sort of political agenda.

Sunday, 24 June 2018

The Amaranthine Lyceum - intro bits

So, the l-space project I mentioned here continues to take shape. I've settled on a name, too: The Amaranthine Lyceum, which I think sounds suitably archaic. It's still in the early stages, but here's some stuff I've written so far.


Between Locations
Locations are simply points of particular interest. Between them, the Lyceum sprawls out, a network of corridors and rooms all lined with books. Nothing interesting; if it was interesting, it would be a location.
Travelling from one location to the next is quick. It takes about a turn (ten minutes). Doors are not locked in the Lyceum, nor are there particular obstacles to exploration unless a location indicates it.

Life in The Lyceum
The lyceum is entirely indoors. There are no windows, no signs of a theoretical ‘outside’. Some locations are lit, by fireplaces or candles or soft gas lamps, but the bulk of them are dark, as are the spaces between. Explorers will need to bring their own lights to explore.
In some locations, food and drink appears if left unobserved. Presumably, the Librarians replace it, although where they’re getting it from is unclear.
The whole place is incredibly flammable. All that dry paper would go up in a flash.

Searching For Specific Books
The most obvious reason to explore the Lyceum is to find information. For any given question the PCs might want answers to, assume that the answer is in the Lyceum somewhere. Likewise with specific books, texts and so on.
When the PCs enter the Lyceum, they can declare they’re looking for a given piece of information. Track the player’s progress towards finding a specific work using the following method.
Give the party as a whole a Progress score, that tracks how close they are to finding what they want. This single score encompasses all the relevant factors: cross-referencing from other related texts, following rumours, making deductions about the layout of the shelves, and so on. Any factor that might bring the party closer to or further away from what they want to know is abstracted into this score.
The Progress score starts out with a value equal to the highest Intelligence in the party. Various events, encounters and locations will cause the Progress to rise and fall. 
For any given piece of information sought,   the GM must set a value for how hard it is to find.
· Basic information found in most good libraries in the real world has a target of 20.
· Slightly specialist information, the sort you’d need to find specific experts or collections for, has a target of 25.
· Obscure information, the sort of thing known only to a few scholars  and jealously guarded, has a target of 30.
· Information that has been forgotten entirely in the real world has a target of 35.
· Information that has never been uncovered in the real world has a target of 40.
The PCs find what they’re looking for as soon as they meet two criteria at the same time:
1. Their Progress score is equal to or higher than the target value for the information they want.
2. They are at a depth equal to the target value minus 20. (IE if the information has a target of 25, they must be at depth 5 or more.).

The Librarians & The Great Avernean Calculation
The Lyceum is inhabited by its own peculiar race of custodians, known only as the Librarians. Diminutive figures, clad in figure-concealing robes, they rarely speak or interact with visitors, instead hurrying about their tasks. Perhaps the Lyceum created them to inhabit it; every library must have librarians, after all. They tend to its structures, like gardeners almost, and pursue more esoteric goals.
The Librarians are split into 5 orders; the red, yellow, black, white and grey librarians, each distinguishable by the colour of their robe. 
The red librarians see to it that the physical structures of the lyceum are maintained; they see to it that the shelves do not break, that the lyceum’s corridors do not catch fire, and that the ceiling stays up.
The yellow librarians tend to the books themselves, repairing and restoring them as necessary.
The black librarians are tasked with the lyceum’s doorways. Whilst this covers the doors within the lyceum itself, more importantly, it also deals with the doorways out into the real world. They keep the doors open (or at least open-able) on their side, and construct further doors into the real world wherever sufficient knowledge accumulates.
The white librarians deal with corralling souls. The lyceum attracts visitors, and is not without its dangers. The white librarians collect and manage these souls, filing them away as if they were perfectly normal books. These souls, now compressed into a simple, easily managed form, become phantoms.
Lastly, the grey librarians see to it that the Great Avernean Calculation be continued, maintaining the Calculation Engines, Phantom Databanks and Sheol Computer itself.

Phantoms are a form of lesser, immaterial undead. They are the soul of one who has passed on, stripped of humanity or emotion. All that is left is memories and information, condensed into a greasy whisp that hangs in the air like the smoke from a snuffed-out candle. Most phantoms have little power to act or think, and are hardly beings in their own right. The white librarians store them in bottles and pump them through glass tubes.

The Great Avernean Calculation is the overarching goal of the librarians of all orders, although only the grey librarians interact directly with it. What the calculation might actually be is hard to say; it exists in a scope that is so huge and complex that any attempts to divine its purpose produces incomprehensibly incomplete results.
What is known, at least to the librarians and those who study them, is that the calculation will, one day, reveal some grand truth about the universe as a whole. Matters of the soul, the written word, entropy, and information play into it. The calculation is far from complete, but every day the vast information-processing machinery of the Lyceum - through which the librarians scurry like ants through a glass maze - explores and finalizes ever more specific details, and over the course of centuries the entire answer is brought into focus.


Monday, 11 June 2018

On Cosmic Horror

The core of cosmic horror is this: it takes the audiences assumptions about how the world works, and subverts them by positing a world where those assumptions are tragically wrong. I'll use three examples to discuss this: Arthur Machen's The White People, HP Lovecraft's At the Mountains of Madness, and lastly Chaos in Warhammer 40,000. 

So, The White People.
Machen was writing for an audience who were probably good, mild-mannered Christians of the peculiar British sort that are very genteel and civil and pleasant. Tea-With-The-Vicar Christians, of a sort I get the impression was a common position at the end of the 19th century. 
Right away, Machen starts taking this apart. The story opens with a discussion on the nature of good and evil - 'Saints' and 'Sinners' as the characters discuss it - and suggests that most people are neither good nor evil, just a sort of muddy mundane neutrality. To be truly Good or Evil is a spiritual pursuit that requires great dedication and is, inevitably, supernatural in nature*.
It goes on to illustrate this point with the story of a young girl being corrupted by Evil. The story mixes in folklore, deep history, witchcraft, fairies etc etc. It paints a picture of the natural world as being innately wicked and sinful, an active spiritual force. There are sexual undertones, and hints and an established cult. 
So why did it work as a story? It subverts that Victorian understanding of the world in nice, simple, Christian terms. It presents as our great sinner not some horrible corrupt faustian figure, but an innocent child frolicking through the woods and streams of the English countryside. It portrays Evil as a spiritual abyss that one might plunge willingly into, but that you could meet a truly Evil, corrupt person and have no idea; indeed their deeds would not seem particularly unpleasant since the Evil is an inner spiritual journey. It suggests that one might have a journey of personal revelation where one comes to [pan/satan/the black man in the woods/the fey/whatever the fuck it was in this] that is every bit as deep and involved and intense as the relationship with Christ that makes up the Christian experience. 
It's a fairly simple story, but the way it presents an inversion of Christian spirituality that seems innocuous but reveals a corrupt core with just as much spiritual strength and power as anything Jesus might be capable of... I can see how it would have been unsettling.

I take The White People as my go-to example here, but this subversion of Christianity appears in other works by Machen (The Great God Pan is the most famous example), and similarly influences works by other Weird writers of the time such as Algernon Blackwood.

(*Could this be an inspiration for alignment systems in RPGs? Perhaps. Certainly, I like to tie 'chaos' in my cosmologies with the picture of nature-cults as supernatural evils depicted here. Druids should be chaotic IMHO. But I digress.)


Next up, let's look at At The Mountains Of Madness.
I'm just going to assume that if you read this blog, you've read this story. Lovecraft takes the ideas that humanity and human civilization are the pinnacle of evolution, that we matter and are important, and rips them apart. Humans are insignificant, existing only briefly compared to the might empires of aliens to which Earth is just an outpost. We are a byproduct of ancient aliens, an accident, a mere flash in the pan. Furthermore, it shows civilization as self-defeating; the Shoggoths' utter destruction of the Elder Things' culture rips down any comfort we might take by transferring our 'loyalty' to the aliens who accidentally produced us. They don't matter any more than we do. Things just happen, there is no 'point' to evolution, all this is just happenstance.
Which, again, when Lovecraft was writing, was shocking. The assumptions that humans were the pinnacle of evolution, and [western] civilization was the apex of human history were quite effectively demolished in this story. Hence, horror.
This takes things a step further. As Christian influence starts to fall away, we get more rationalist positions emerging and Lovecraft basically takes those positions and pushes them to their horrible extreme. 


Moving on, let's consider a more modern example: Chaos in the Warhammer 40,000 setting.
This seems to be written with a particular set of secular western ideals in mind: the sort more common in Europe than America, perhaps more common on the political left than the right, and disproportionately represented among nerdy types. IE: Games Workshop's writers and audience in the late 80s when 40k was being written. Here are those values, bullet-pointed:
  • Science can explain everything.
  • There is no supernatural.
  • The world does not care about you.
  • There is no God taking an interest in you.
  • Nothing you do is particularly important.
  • With no real significance to your actions, hedonism is a perfectly good goal.
  • Things are basically OK.
It's a sort of casual rationalist nihilism. Bland secularism that asserts that 'hey, it's all meaningless, so buy stuff and be happy, it's not like you're being judged'.
The role of Chaos in 40k utterly subverts this:
  • Science can't explain a world where things happen at the whims of mad Gods.
  • The supernatural is there, is uncontrollable, and is intrinsically tied to the physical world.
  • The supernatural is shaped by the souls of you and people like you.
  • There are Gods. They care deeply about you, they hunger for your soul. They are horrific.
  • Your actions lend power to these Gods, and can attract their attention.
  • Hedonism is a sure route to being subverted by these Gods; so are most other approaches to Nihilism (despair, rage and Nietzschian ambition).
  • You are totally fucked by forces beyond your control that are coming for you personally.
Worth noting, the four chaos gods (slaanesh, nurgle, khorne and tzeench) represent four responses to nihilism (hedonism, despair, rage and ambition). This is why there aren't chaos gods of (say) Death or Romance or Leadership.
Chaos in 40k posits that in fact, there are Gods, and they are watching you, and they have an interest in you. They want your soul, they want you to reach out to them. They have gifts for you, if you only let them in. 
It's like... 40k looks at the rationalist/atheist/materialist/secularist position which arises as a response to Abramic religion, that we see in the modern day. The rejection of the idea of a personal God and Savior that's waiting for you to open yourself up to them. 40k takes that position and says 'no, that's bollocks, there are Gods'. And then takes the Abrahamic position and says 'no, that's also bollocks, because the God you're worshipping is an insane monstrous thing that wants to eat your soul and turn you into a tentacle monster'.

Remember the White People? How it describes a world where, just as one can have a relationship with a benevolent God and all that Christian spirituality happens, one can also have a relationship with forces of wild, corrupting Evil that is just as deep as the Christian version.
40k says 'well, what if you only had the Evil option?' What if Machen's Pan was the only deity, and it was everywhere?


So, this is a gaming blog. How to make this gameable?
I play a lot of LotFP, and LotFP is the main influence on my other OSR writing. Weird fiction and cosmic horror influence the worlds I set up for my players. 
If your approach to cosmic horror is merely 'there are space aliens, they have tentacles, lose 1d8 San', you're failing at it. To make it work, you need to use this framework:
  1. Take some basic assumptions your players have about the real world out-of-character.
  2. Work out what the horrible inverse of those ideas would be.
  3. Slowly reveal that the world your game takes place in is one where the ideas from point 2 are correct.

So lets workshop this. Take some ideas that our players will probably hold, based on our current cultural climate.
  • Humans control the world and Nature, through science, industry ect.
  • Humans are destroying the Natural World (see: climate change, extinctions, etc etc).
  • The Natural World is a passive thing that we are wrecking.
  • Nature is a good thing that should be cherished and protected.
Now, let's invert these:
  • Nature is something humans can never truly control, no matter how advanced our science.
  • Humans don't pose an existential threat to the natural world; rather the Natural World poses an existential threat to humans.
  • The Natural World is an active force that seeks to undo humanity's works and which is stronger than us.
  • Nature is brutal, horrible, savage, untamed; it does not need protecting from us, but we need protecting from it.
What would a game set in such a world be like? A world of ruined, overgrown machinery. Parasites and sicknesses that inflict body-horror on humans. Most enemies are features of the ecosystem, not 'people' or spiritual forces. Survival in the wilderness is difficult. Plants and wild animals as dangerous threats. Humans as unwelcome parasites that the immune-system of the green world will soon purge. The wilderness as a tidal-wave of crushing savagery that will overwhelm human settlements.

Oh look, it's The Willows. Or The White People. Or Ynn. Or Wolfpacks. Or Frostbitten & Mutilated.
So, yeah. 
If you want to do cosmic horror, maybe use that stuff as inspiration. 

Saturday, 9 June 2018

Dungeon Concept - L-Space

With apologies to the late Terry Pratchett, who's ideas I'm unashamedly nicking.

Here's the basic foundation from the diskworld novels.
Books are collections of knowledge, and Knowledge = Power
Anybody who has studied high-school physics knows; Power = Energy over Time
And according to Einstein, Energy and Mass are interchangeable, and mass warps space time.
So the power contained in a book will warp spacetime as time progresses. That's just logic, right?
Ergo, any sufficiently good library will have highly warping effects on the space it occupies. To quote Pterry,  "[a] good bookshop is just a genteel blackhole that knows how to read." The books go on to posit that all sufficiently dense libraries connect into one huge extradimensional 'L-Space'.

So, there's your setup. A library dimension accessible through any good enough normal library. Corridors and shelves that wind around and fold in on themselves and multiply fractaly. A non-euclidian layout with imaginary dewey-decimal numbers.
If I end up making this, it'd be a similar setup to how I did Ynn. Procedurally generating points of interest that form a linked network that goes ever deeper, and gets weirder as you get deeper. The same basic structure (location + features, roll for events every turn, navigate by 'Go Deeper' vs 'Go Back' vs 'Explore Here', depth shifting you up and down the random tables).

So, why is this interesting? Well, L-space is effectively a genteel megadungeon. Remember, Knowledge = Power, and Power Corrupts. Thus, the warping effect of the books on the world around them will produces all sorts of interesting weirdness. Monsters might be transformed librarians, characters escaped from the books written about them, animated books, things that have made their way in from other dimensions via shared L-Space. Weird features like rooms filled with candles, spacial anomalies, sealed vaults of censored materials. Spellbooks that have gotten even stranger under the altering effects of L-Space.


Why go in? The place is obviously totally packed with books, so in order that it's not a total XP-For-Gold bonanza, I'd say that only particularly noteable books are going to be worth XP. On the other hand, L-Space contains all the books you could want. Need an atlas that maps that new continent you're voyaging to? Go to L-Space. Need the historical records of that ancient evil? L-Space. Looking for a particular rare spell? L-space. Dictionaries of dead languages? L-Space.

So yeah. Not sure when I'll develop it, but the idea is there knocking about in my head.

Wednesday, 6 June 2018

Duels in OSR

This is inspired by my work on The Dolorous Stroke, but adapted for OSR games.
Here's a system for when two characters duel.

Duelling requires that two combatants agree to one-on-one combat, and are not interfered with by any third fighter. Once the duel has begun (which might be in the midst of a larger fight), the combatants continue to fight round-by-round as normal, until the duel ends. The duel might end because one duellist is slain, because a third party interferes, or because one duellist admits defeat or tries to break away from the fight.

The fight is resolved normally, with both sides rolling to hit each round on their action. 
At the start of each round, however, both sides must choose their tactic for that round; either Push, Parry or Feint. Each chooses secretly and reveals simultaneously, like for 'rock-paper-scissors'.  Compare each fighter's tactics, which will modify the rolls for the round.

Parry beats Push, as the parrying character turns away the obvious attacks of the push. The character who parried gets +3 AC.
Push beats Feint, as the aggressive push forward batters through the attempts at finesse. The character who pushed does +3 damage if they hit.
Feint beats Parry, as the feinting characters creates openings to strike past their enemy's guard. The character who feinted gets +3 to hit.

If both sides Parry, then the duel becomes a defensive stand-off. Both characters get +3 AC.
If both sides Push, then they just batter at each other furiously for the round. Both characters do +3 damage if they hit.
If both sides Feint, then the duel becomes a complex dance of strikes and counters. Both characters get +3 to hit.

* * * 

Feint/Parry/Push are named for sword-vs-sword duels, but you can use the same mechanic for other 1-on-1 fights. For example:
A joust has Evasive (+3 AC), Aim for the Body (+3 damage), and Aim for the Shield (+3 to hit).
A firefight with both parties shooting from in cover has Hunker Down (+3 AC), Shoot Recklessly (+3 damage), and Aim Carefully (+3 to hit).
A fistfight has Back Up (+3 AC), Swing Wildly (+3 damage) and Dirty Blow (+3 to hit).
And so on.

* * *

What's my reasoning? I wanted 1-on-1 fights to have an extra layer of tactics to them, rather than just being 'roll to hit' each round. In my experience reenacting and larping, a 1-on-1 duel is a fairly tense affair, with both sides trying to read the other so they can take advantage of their mistakes. So, the rock-paper-scissors model works well here: predict what your opponent wants to do, and you can capitalize on that.
For predicting your opponent to be viable, there needs to be some asymmetry between the 3 options, otherwise which option is picked will be basically a 1-in-3 random chance. So, each option gives a different advantage if it succeeds, motivating you to pick different options depending on the situation. In a round, the duelist must decide if they care most about not getting hit, about damage if they hit, or about successfully landing a blow at all. If you're losing badly, pick Parry to go on the defensive, for example. Since different combatants will have different talents and priorities, you can take a good guess at your opponent's tactic based off that. 
Likewise, it's possible that the situation can make one tactic obvious for you: perhaps your down to 1HP and any hit will drop you. The obvious move here is to parry, for the AC bonus, but your opponent knows that and so will want to go for a feint in order to beat your parry and get that last hit in: if you instead go for a push, you catch them off guard, negating their feint entirely and getting extra damage in.