Could you please be more specific? But I think yes, for instance some abilities affect only Frostlings. So filters do exist to limit effects to some units.
The only mechanic I know of that allows to transfer something from tactical to strategic map is mind control (MC). It's possible to give some stuff to MCed units. It's also possible to give permanent properties to units through at least touch abilities (Eomolch did it in the Racial Heritage mod). So depending what you want to do, might be possible.
Unlocked by a research and giving an ability to unit types => that's called Empire Upgrades.
As far as I know, there is no filter for the number of medals.
Unit tiers also cannot be filtered for as far as I know.
Okay I will give more context, for 1) what I mean is a skill like bone collector's collect bones, but imagine it from a perspective where it can 'collect' different units and give different buffs depending on that. I got close to finding a solution by making a skill with multiple targeters which all have separate prerequisites and all have "must be valid" as false so you can have only one of the targeters be true for the ability to work. The issue I encountered is a targeter will target the unit it's casted on, rather than the unit I want to receive the stats from using the ability. I wanted it to be cast on a unit of an opponent and then give stats to my unit depending on what unit it is cast on (for example dmg for infantry, hp for irregulars, ranged dmg for archers etc). The only problem I have is I can't figure out how to make the property go to the caster but the targetted to mark the enemy (the skill is supposed to be a 'marked for death kind of skill where it marks the enemy and if they die my unit gains a property which gives them a stat bonus). Is it possible to do that, and if so do you have suggestions for a suitable work-around to improve my initial idea, I think it might be doable but I also feel like I'm missing 1 singular puzzle to do it.
for 2) I meant something like "on kill" abilities or abilities like the aforementioned "bone collection" but that I already figured by just file searching and analyzing so less help needed with that part.
for 3) I figured a suitable work-around is to make a property that all units will get as they hit champion rank, so I will just add a property called 'champion' that does nothing but can be used as a prerequisite for the ability to be applied to them, I think that's doable but again need to test it more thoroughly later.
Edit: I think something
very similar to "mark blood sacrifice" would work perfectly, but I need to find a way to make it target the killer unit instead of just boosting the entire army of the player who kills the unit which I'm not sure how to do.
Edit2: This I need some insight with, but maybe I could do it so that the unit who cast the skill gets a property which lasts until the end of their move like "absorbing power", and then put on the on death status effect which is placed upon the enemy a prerequisite that only units with "absorbing power" are affected, a bit of a crude work-around but maybe would work?
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