# Jul 14, 2019, 2:51 pm HideInspired by the recent post about weapon types, and thinking about systems already IN IVAN, I suggest we implement knockback as a combat mechanic. I'll break this down in 4 parts: 1) where it already exists, 2) suggestions on how it could be implemented, 3) ways it could change the PC tactical meta, 4) ways it could be implemented to create new challenges.
1: Knockback is already in the game. Kicking. When you kick a monster, sometimes they are knocked "off balance" and stumble back a square (or slam into an obstacle). In addition, I believe strong explosions sometimes push things away from their center. So, the code is already there; it would just need to be updated, tweaked, and implemented in more places.
2: As mentioned above, currently, kicking is the only way to cause knockback. I suggest expanding this effect to apply to any attack, with the percentile chance of it firing dependent on three factors: First, the damage of the attack; second, the weight of the weapon used to make the attack; third, the roundness of the weapon. A formula could look like...
A,a,B,b,C,c = < Numbers used below to weight the modifier towards some values, for the purpose of balance. > Modifier = A(STRENGTH)**a + B(DAMAGE)**b + C(ROUNDNESS)**c # This value will rise for high knockback items. Minimizer = 1000 # This value is just a placeholder. I don't know what scale Modifier would be on. See below for this number's purpose. ChanceToKB = Modifier / (Modifier + Minimizer) # The chance to cause knockback. Will never reach 100%.
A note on all this: I'm not sure how unarmed strikes are currently handled, or what their values are for roundness or weight. But, punches and kicks should be very round, and bites should not be very round at all. Further, for realism (and because arms and legs are astoundingly heavy) perhaps the weight might be set to half the weight of the attacking limb.
A related quantity would be how far an enemy is knocked back on a successful knockback. This distance should be calculated in a manner similar to Modifier in the above equation... but would be mitigated by the weight of the target. INCLUDING the weight of their armor. However, carried (backpack) weight should NOT provide benefit - if anything it should make you more likely to go off balance. Being knocked back, in addition to pushing someone out of place, carries a chance of throwing someone into obstacles, which can cause additional damage.
Now, what does this parameterization do? It favors heavy, round weapons (such as maces and hammers) wielded by strong characters, giving them a chance to cause extra damage by slamming enemies into walls. It also gives some benefit to large slashing weapons, such as axes and two-handed swords. It gives less (but not no) benefit to small fast weapons - they don't really need the help anyways As a side effect, piercing weapons (such as spears) do not gain much from this mechanic. Further, this increases the defensive benefits of heavy armor in an indirect way, which is, IMO, the best way to buff something.
3: What does this do to the PC equipment setup? Well, it gives a much-needed boost to heavy weapons while giving a minor boost to small-weapon builds; in effect, it's an unequal buff to all PC gear builds. It does mean that sometimes you'll knock someone back when you don't want to - but that's rarely a problem, I think, except when you finally manage to get Izzy in melee range in a hallway, then you smack him and send him flying...
It also gives an unequal debuff to all armor setups, applying more heavily to light armors. However, again, these armors don't really need any help since they are already strong. (Besides - if you don't get hit, you don't have to worry about knockback at all )
4: How can this be used to challenge players in new ways? Monsters can be designed all around the knockback mechanic. Bears and golems could knock PCs around all day, throwing them against walls and through doors. Dungeon levels with treacherous footing become more dangerous when you have to fight big strong knockback-happy monsters along the way. (Probably don't want to put these kind of creatures close to insta-kill terrain though... that's a recipe for salt.)
Right. That's all I got.