Polyraptor + Forerunner of the Empire + Cathars' Crusade

Polyraptor

Forerunner of the Empire

Cathars' Crusade

How it works

1. Deal damage to Polyraptor.
2. Polyraptor triggers, creating a token copy of it.
3. The Polyraptor token enters the battlefield, triggering Forerunner of the Empire's second ability and Cathars' Crusade.
4. Resolve the Cathars' Crusade trigger, putting a +1/+1 counter on each creature you control.
5. Resolve the Forerunner of the Empire trigger, dealing 1 damage to each creature.
6. Each Polyraptor you control triggers.
7. Resolve a Polyraptor trigger, creating a token copy of it.
8. Repeat from step 3.

This delightful loop relies on a self-sustaining ecosystem of damage, replication, and growth. Once you deal that initial spark of damage to Polyraptor, its enrage ability creates a fresh token copy of itself. The entry of that new dinosaur triggers Forerunner of the Empire to deal 1 damage to each creature, which in turn hits all your Polyraptors to spawn *more* copies. Meanwhile, Cathars' Crusade ensures that every creature you control grows larger with each iteration, insulating your army from the Forerunner's ping and compounding the explosive power of the combo.