I made a valiant attempt at a balanced weapons/armor mod but its a LOT of work finding a good system.  In the end I am trying a different route then I might try the weapons/armor mod again.

What new tags? 

UnitStats are great for Calcs in Game Modifiers, but those can only be used in SpellDefs. 

So yes, you can set up a weapon that has an active offensive ability vs mounted units, but not an intrinsic bonus.

IRL the power of spears and pikes vs mounted is generally considered a defensive one, as they are set to break a charge.

Now that I think about it, maybe you could set up spear to BattleAutoCastSpell to do some extra damage vs mounted units on the first turn.

Hmm...

Spears don't need to have a bonus VS mounted. Mounted doesn't necessarily give a bonus to melee. So I don't think its necessary to introduce counters and paper-scissor-rock type scenarios. The spears in this game look more like early styled ones. Pretty simple pointed heads. Averange length but sturdy shafts. The sort of things the Greeks would have used (just look at the defensive perk!).

Spears were mostly good against cavalry due the the shear mass they could be produced in. Requiring little metal and being able to just POINT them at the rider general did the job of stopping cavalry. The pike square being the prime example. Later example are things like the pike and shot which was like a big pike square, but with guns too.

What you'd be wanting is 'specialist' equipment maybe. Something like a halberd or bill, which look like a spears. Could deal bonus damage to mounted units. Due to being able to dismount them and then 'deal' with them. Special attack replaced with Dismount Foe?

You can also add a revenge damage to spears if attacked by a mounted unit.  You have to use the damage reflection modifier and then used the tag you have listed above.  SO basically if a unit is mounted and attacks someone wielding a spear they will take some of the damage they did to the spear wielder even if they are immune.  If you want to make it punitive for mounted units to attack spear set the damage reflection percentage to 200% or higher such that a mounted unit attacking a spear unit is deadly.

@abob

Ah yes, I had forgotten about that little trick.

I completely retract everything I have ever said.  Ever.

That's fair enough. I suppose what counts as "fun" in this context differs for quite a few of us. I do not dislike spears' special abilities because it is "unrealistic" (as if throwing fireballs, for example, were realistic...), but because it feels gamey, and for me, at least, that is not fun. I would hate to have to mod it out and mod bonus vs mounted in, because I am admittedly an idiot and cannot mod to save my life.

I think I have a writeup on how to do revenge damage on one of the threads a while back that I was showing to Heavenfall, that combined with the plus damage to mounted units would be an interesting counter to mounted units.

If we add revenge damage to all weapons, won't this change the combat system to one where each 'attack' is also incorporating a 'defence', so making it a fight, not a free hit? 

That might be the basis of an interesting battle mod right there?

Actually this should work extremely well. If the spear unit is damaged and easily killable, charge them and ride them down. If they are formed and ready, the cavalry will be smashed. Gives the anti-cav effect of 'formed' spears, while still allowing them to be vulnerable if unformed or damaged.

I don't mind spears the way they are now, lining up a spear unit with 2 enemies can be more challenging than it sounds.  I would have liked Spears (or high end spears) to have preemptive counter-attack during the first turn which would balance out the Charge ability which mostly favors mounted units.

i was thinking something like this as well.  even a 6 ft spear will give you a range advantage over non-polearm weapons.  there would definitely be more opportunities to use this and I wouldn't have to break up my phalanx.  (and the pike research could give it an even greater range bonus.  ok, i may have to have a crack at modding this).