Rite of Passage + Triskelion + Loading Zone

Rite of Passage

Triskelion

Loading Zone

How it works

1. Activate Triskelion by removing a +1/+1 counter from it, dealing 1 damage to itself.
2. Rite of Passage triggers, putting two +1/+1 counters on Triskelion.
3. Repeat an arbitrarily large number of times.
4. Move to the next turn, removing all damage marked on Triskelion.
5. Activate Triskelion by removing a +1/+1 counter from it, dealing 1 damage to any target.
6. Repeat step 5 as desired.

This ingenious loop turns Triskelion into a self-fueling engine by leveraging the passive damage-trigger of Rite of Passage alongside the counter-doubling replacement effect of Loading Zone. Whenever Triskelion pings itself for 1 damage, Rite of Passage attempts to reward its survival with a +1/+1 counter, which Loading Zone immediately doubles into a net gain of two counters. Because you generate more counters than you spend, you can arbitrarily grow your creatures and stock up an infinite supply of ammunition before turning Triskelion's fire outward toward any target you choose.