Messages

I've read that only cards with "destroy all creatures" are the only way to destroy hexproof, but was curious about this being another possible choice.

Can cards such as, perilous myr and goblin arsonist effect/ability be used towards a hexproof creature, like invisible stalker or dungrove?

Ty.

When revenge is hard casted or played as miracle, does the counters have to be put out to a target immediately, or anytime before the attack takes place?