Keyword: Enrage

Enrage — Whenever Bellowing Aegisaur is dealt damage, put a +1/+1 counter on each other creature you control.

When Apex Altisaur enters, it fights up to one target creature you don’t control.
Enrage — Whenever Apex Altisaur is dealt damage, it fights up to one target creature you don’t control.

Enrage — Whenever Ranging Raptors is dealt damage, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Enrage — Whenever Ripjaw Raptor is dealt damage, draw a card.

Vigilance
Enrage — Whenever Urban Daggertooth is dealt damage, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Enrage — Whenever Vrondiss, Rage of Ancients is dealt damage, you may create a 5/4 red and green Dragon Spirit creature token with “When this creature deals damage, sacrifice it.”
Whenever you roll one or more dice, you may have Vrondiss deal 1 damage to itself.

Enrage — Whenever Vrondiss, Rage of Ancients is dealt damage, you may create a 5/4 red and green Dragon Spirit creature token with “When this creature deals damage, sacrifice it.”
Whenever you roll one or more dice, you may have Vrondiss deal 1 damage to itself.

Enrage — Whenever Ranging Raptors is dealt damage, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Enrage — Whenever Ripjaw Raptor is dealt damage, draw a card.

When Apex Altisaur enters, it fights up to one target creature you don’t control.
Enrage — Whenever Apex Altisaur is dealt damage, it fights up to one target creature you don’t control.