Sorry to come along and play useless pundit, but I am just a little too weak right now to fight my urges...
Well… You are concerned about realism, which afaik, is an important factor for a good portion of this game playerbase, reasson enough to always keep an eye on how rules are projected on the “Real” world.
I’m also concerned about realism, but I prefer to “cook” my suggestions to achieve a balance based on what the players do than what the actions means and ofc how feasible is to implement them.
Size Matters
Using Size is simply an economy decission… Lots of modders (and the base monsters) already come with the tags “Large” and “Huge” to label monsters that are massive and, in theory, a higher menace than regular Z’s at melee range… Coincidently this mobs are also capable of fast movement (To highlight it’s danger level by preventing easy kiting) meaning their muscular mass is considerably higher than the player’s. The whole thing means that a simple code triggered at the knockback maneuver that compares character size vs target size will accomplish this effect with minimum implementation time. The other complex relations in a melee fight (which is basically an interchange of momentum) are controlled by a: Melee Damage Dice & HP pools. As I said on my previous posts, this magnitudes are used in a lot of places in the game… So I prefer to offers suggestions that surgically mimic what I was trying to link with the “average joe” perception which is simply… You can’t expect to move a house by kicking it ;).
That’s why I link “size” to muscular mass on the parry modification… Which is needed to make this monsters to do any kind of damage based on how current melee block/parry system works so modders are not forced to make this monsters masters at melee themselves (They are usually defined with melee skill levels of 10+) to reduce to the max the chance of a dodge to happen. The current paradox is that, against this monsters, the way modders are forced to create them… The best defense is blocking (and been dressed in some armor… Not much) as, due to their impossibly high melee skill, dodges rarely happen. Again, drawing from the “average joe” perception, this time backed up by basic physics, what should happen is that bigger mobs should do more devastating hits but… Slower, which, translated to game terms, should make them EASIER to dodge but able to inflict considerable damage even after a block/parry. This way content creators would be free to unlink destructive potential from precission at triggering that destruction which, in turn, will offer more variety in the kind of enemies (And tactics needed to survive them).
Finnally, the “been grabbed” by a bigger target is required to work in coordination with the “free attack” rule below as, due to how grab works now, it’s just a minor nuissance easily neglected with average levels of player melee skill.
Melee Combat is tiresome
The approach I followed here was much simpler than your concerns… It’s a simple balance factor with ranged combat. Been able to project X ammount of damage at range on DDA is far… far… far more resource draining and bulkier than melee. That’s what STF system is for… In reality is just an “ammo system” for melee the player needs to care about and “reload” by not engaging too many targets at the same time or too frequently. This is my primary goal… Making Ranged combat set of drawbacks to be usefull (at the same skill levels) ALSO against melee-only targets or even explosives/traps to be a must to deal with hordes because the physical extertion barrier would simply prevent the player to keep on going.
As with the above changes… I’m allergic to link multiple subsystems together when offering suggestions, that’s why I contained the STF triggering & degrading effect ONLY to very basic set of melee actions and melee penalties… Easy to code and affecting ONLY melee performance.
Reallistically-wise, when unlinking long-term fatigue from short-term one… The 1st thing I asked myself is why a character in DDA can run at peak speed miles without having to slow-down… That’s why I ultimately linked Exhaustion to Pain (A well known and prentifully tested mechanic already existing on the game) because, atm, is the only way to slowdown a Player (and tbh, the reasson behind 90% of my deaths)… But notice how I’m not including “X movements in a row” in the STF triggers because I don’t want to alter that delicate balance needed for a ranged fighter… One change at a time.
Returning to the nature of fatigue… Indeed there are a lot of physical labor jobs able to trigger STF but there is a capital difference between ALL of them and melee…
…Your enemy actions control your fatigue (Specially if it’s a sapient one). You can’t “administer” your fatigue spenditures as with any other physical labor were you can take a “rest”… If you “rest” while defending yourself you are going to end dead (I don’t know if you have experience with Boxing tactics… But playing with/against muscular fatigue is a key factor, specially in higher weights. It’s just an IRL example of how important this effects are for some1 that doens’t have the luxury to ask for a “rest”). That’s why, everything considered, imo, melee is entitled to be treated in this special way as it’s the game activity were the stakes are higher and, atm, is simply too efficient damage and resource-wise.
One of the things about attacks of opportunity is that they are justified as being free because the victim stops defending themselves and also stops being a threat.
AOO may be justified with different “realisms arguments” under different games but, in my case… I just pay attention, again, to the effect they cause on players’ decissions which is simply to make them pay more attention to which enemies they get close to (There are plenty of flaws on the different PnP ruleset that use them… Most linked to the lack of real consequences, but that’s a discussion to be held somewhere else). That’s what I care about and what DDA melee lacks… Stand your ground, wait for your enemy to get close and then hit’n run is the safest approach to melee in DDA… The fact that a lot of “pseudoattack” rules have been implemented (like leaping enemies, grab or the “hit-on-the move” effect that happens with the attacks that are “cheap” enough) is a clue that there is a will to “spice up” this basic premise. Again, content creators have their hands tied when trying to make particularly troublesome targets that’s why adding a tag that clearly labels an enemy as a danger to kill/disable before trying to move away is needed.
You bring a set of in-game enemies that could be candidates but… You are just focusing them as single entities… Instead try to think in whole scenarios. What if that usually unremarkable Feral Hunter is able to grab, leap & free attack you… By itself is just another easy to kill zombie but… What happens if it decides to leap to establish contact while you are ALREADY in melee range of a Hulk? Mmmm… A carefull character will hesitate into going melee with a combo like this around and would have to take decissions (Like swaping to less damaging, but potentially incapacitating attacks to prevent the Hunter to keep him in place while the Hulk smashes him/her or… Simply swap to ranged combat to take down the enemies even if they can’t retaliate at range)… What if the Hulk himself is able to grab and free attack? Wouldn’t its size advantage be a lethal combo? I prefer to keep things simple… A content creator doesn’t have to care about tweaking different magnitudes, with this 2 (optionally 3) tags can clearly label a monster as “Watch what you do when close to this baddie” ;).
Regarding my own personal preference on how to justify AOO with “realism”… Observe how most land-based predators take down their preys (Specially when they are of similar mass)… They are always reluctant to go full out when their enemy is facing them, is precissely the exact moment their prey tuns back and initiate its flee attempt when they lunge forward to bite/claw it on the back.
