Farmstead Gleaner + Elemental Mastery + Mana Echoes

Farmstead Gleaner

Elemental Mastery

Mana Echoes

How it works

1. Activate Farmstead Gleaner by tapping it, creating a number of 1/1 Elemental creature tokens with haste equal to its power.
2. The Elemental tokens enter the battlefield, triggering Mana Echoes that many times.
3. Resolve the first Mana Echoes trigger, adding C for each Elemental you control.
4. Repeat step 3 for each remaining trigger.
5. Activate Farmstead Gleaner by paying 2 and untapping it, putting a +1/+1 counter on it.
6. Repeat.