Horrible Hordes

Rampage is a triggered ability. “Rampage N” means “Whenever this creature becomes blocked, it gets +N/+N until end of turn for each creature blocking it beyond the first.” (See rule 509, “Declare Blockers Step.”)

The rampage bonus is calculated only once per combat, when the triggered ability resolves. Adding or removing blockers later in combat won’t change the bonus.

If a creature has multiple instances of rampage, each triggers separately.