Genku, Future Shaper + Crystalline Crawler + Cryptic Trilobite + Doubling Season

Genku, Future Shaper

Crystalline Crawler

Cryptic Trilobite

Doubling Season

How it works

1. Activate Genku by paying 3, putting two +1/+1 counters on each creature you control due to Doubling Season.
2. Activate Cryptic Trilobite's first ability twice by removing two +1/+1 counters from it, adding CCCC that can only be spent to activate abilities.
3. Activate Crystalline Crawler's first ability twice by removing two +1/+1 counters from it, adding .
4. Repeat.
5. Once you have infinite C, you may forego removing counters from Cryptic Trilobite.

This clever loop transforms Genku, Future Shaper's activated ability into a self-sustaining engine by leaning heavily on the replacement effects of Doubling Season. When you pay to put counters on your creatures, Doubling Season doubles them up, allowing Crystalline Crawler and Cryptic Trilobite to comfortably harvest more counters than you spend. You then tap those two mana producers to filter your restricted energy into the exact colored mana required to feed Genku, Future Shaper over and over. Because the net result leaves your creatures bigger while generating an excess of colorless mana specifically reserved for abilities, you can repeat the cycle infinitely.