Ornery Tumblewagg + Crystalline Crawler + Aggravated Assault

Ornery Tumblewagg

Crystalline Crawler

Aggravated Assault

How it works

1. Activate Ornery Tumblewagg's saddle ability by tapping Crystalline Crawler, causing Ornery Tumblewagg to become saddled until end of turn.
2. At the beginning of your combat phase, Ornery Tumblewagg's first ability triggers, putting a +1/+1 counter on Crystalline Crawler.
3. Declare Ornery Tumblewagg as an attacker.
4. Ornery Tumblewagg's second ability triggers, doubling the number of +1/+1 counters on Crystalline Crawler.
5. Move to your postcombat main phase.
6. Activate Crystalline Crawler's first ability five times by removing five +1/+1 counters from it, adding 3.
7. Activate Aggravated Assault by paying 3, causing you to untap all creatures you control and to get an additional combat and main phase after this one.
8. Repeat from step 2.
9. If Crystalline Crawler begins the combo with four or more +1/+1 counters, this combo will net infinite +1/+1 counters on it and colored mana, which will allow you to target any other creature(s) using Ornery Tumblewagg's triggers.

This clever loop turns Ornery Tumblewagg and Crystalline Crawler into a self-sustaining engine by letting the Mount's combat triggers aggressively multiply the counters on the Crawler. Once those counters pile high enough, you can strip them away for mana to fuel Aggravated Assault, which grants the extra combat phases needed to repeat the process indefinitely. Because Aggravated Assault untaps everything in the bargain, Crystalline Crawler is left ready to be tapped for the saddle cost, letting Ornery Tumblewagg kick off the next cycle with ease.