I'm working on a map with a special unit called a Zerg Stalker which is represented by Infested Kerrigan. I was wondering if there is any way to force the player to research spells for Stalkers (Cloaking, Ensnare, Psionic Storm) before they can be used. (Note that in this map spells are 'researched' in a totally different way; the spells won't be researched at a Covert Ops/Queen's Nest/Templar Archives, but by moving a unit.)

Well, one possible way you could do this is by making it so that certain spells require X amount of energy to cast. And the more you research, the larger your energy capacity will be (and this will be set by the modify unit energy action.) There are many drawbacks to this though as I'm sure you might've realized already. But I think there might be some EUDs you can use to detect a unit's energy level and prevent you from going over that number. Like say psionic storm costs 50 mana, if you haven't "researched" it yet, then you can trigger it using the EUDs so that if your mana is exactly 49, just set it back to 48. Again I'm not sure if this is possible so you're going to have to see.

Yeah other than those workarounds there's no way because heroes always have their abilities researched except when you disable the tech. But then there's no way to activated it ingame. Obvious exception: Giving to another player.

As in, I disable Psionic Storm for Player 1 and give Player 2 Psionic Storm tech, then create a High Templar for Player 2, give it to Player 1, and remove the Templar? Would that work?

Nope, he means Giving it from player 1 who does not have psi storm researched to player 2 who DOES have psi researched, then the psi would work.

The only solution i see for heroes is just the energy trick thing.

You could do it without EUDS by having a death count that increases at the exact same speed that the energy does, and then when it gets to 50 (which is the energy to cast psi hallucianation) you could always set it to 49, then when he casts psi storm (Detecting this could be a problem, but other units might work) set the death count back down.

Okay, can do. Thanks. Detecting it would be a problem, as you said, but... hey, this is staredit.net. Do we ever let things like that stop us?

Yes. Yes we do.

Note: Theoretically you could use the "rescuable" system right?

I am probably totaly wrong here, but if you find the rate of increase of energy couldnt you in theory know when to stop it at like 49 energy?

Also, and this is probably very lame, one thing you could do is if your main is the Templar and you want him to "research skills" you could just give P1 an unresearched regular templar. Then when in your game you desire him to "research" the skills, replace it with the Hero Version of the templar. Infact, you could put a cap on the energy by making him always have the same energy so when he "researches" again he use that last templar or just remove the cap energy.

Dumb yes, but I am tryin to think

Think about it:
You wait the time it needs to regenerate 50nrg, then set it to 50 all the time.
Then the player casts a psi storm or whatever and instantly gets his energy back.
You really need detection for this.

And about your 2nd suggestion: It's not that bad. There's 1 templar and 2 heroes. You could make the first upgrade level learn him the new spell and/or a ground attack and the 2nd level better hp and damage. Limitation is ofc, that both heroes will have all spells researched, if not disabled.

And the exception I meantioned (give to another player) does not apply here, as you want it for human players, which can't just hop to another player slot.

Hm. I don't really need this for Tassadar, I need it for Kerrigan. (Infested, of course.)

And seeing as this is a RPG-ish map, I can't very well go giving the PCs to comps.

Well, that's my point: Make kerri the last evolution and use templar/tassadar as earlier forms

Ah. I see what you are saying. Problem is I'm already using Tassadar for one of my other heroes. Not to mention, that would really screw up my upgrade system.

Anyway, I'll just think of another spell to use instead of Ensnare.