Hi SergOz,

I myself have written many scripts like this

2 questions,
what will happen if the enemy casts "cleanse"? Or gets cleansed by other effects? (okay looks like that would not result in negative damage)

What does that do?
Is it needed, Could you not just loop all 20 Battlestacks?
Could you not just use BM:G and check for Prayer?
And isnt Prayer specialist not strong enough already :D ?

Another suggestion that is probably safer would be to apply a little bit of bonus damage with attacks, when Prayer is present on the stack and was cast by a specialist.

Good job!