How to make enemy minions cover for a Boss?

Hi there. I've tried Googling and searching through the forums, but I'm just not seeing the solution, so here goes.

In the default Ace battle system, how do you make enemies take the damage meant for one boss enemy? I'd like to do this without scripts, if possible.

I've been playing around with the Substitute Flag and Cover but I must be doing something wrong, because in test battles I can still hit the Boss without the minions taking the damage.

Come to think of it, how do I get an ally to take the damage for another ally? I'm sorry if the answer is obvious, but battles are new to me :/ 

Substitute only works within a certain threshold of HP. I think it's 25%, for example.

On line 645 of Scene_Battle, you can change the value of when the Substitute will apply. Just try to figure out something to your working. 

Use Cover target states to make enemies cover certain targets.


Use Cover Conditions to customize when they should do the cover.


Note that you need to explicitly use a force action to have minions use a skill on the boss in order for the cover target effect to be properly set up.

Thank you for the replies! I was hoping to do this without scripts however >_< I'll take a look at both options and see what I can do. Thank you.

Yeah, there's no way to do it without either using scripts or at least touching the scripts (to say something like "Cover if the ally's Enemy ID is equal to that of the Boss"), because the game's default "Substitute" functionality is applied to a battler and will have that battler cover for ANY ally (including another minion) if the ally's HP is less than 25%.  So go for either Hime's or Arin's solution.

Okay I've decided to bite the bullet and look at Tsukihime's scripts. Cover Target States is pretty straightforward, but Cover Conditions leaves me utterly confused. I don't understand things like "note tag" and "formula" in the explanation page.

Can someone please please help explain to this tired, script-stupid brain of mine how to set it so a battler covers a boss at all times? >_< Or if we must use numbers, how to cover the boss if the boss' HP is 99% and below?

Also, I read here that Force Action has a bug. I am not using Yanfly Core, only Yanfly System's options (no other scripts) so what is this bug?

I would really appreciate anyone's help >_<

Edit: Okay, Fomar helped my script-idiot self out, seen here for those who might have this problem later. Thanks, Fomar!