Elemental Mastery
Born to Drive
Devoted Druid

   Prerequisites

What do I need to start this combo?
All permanents on the battlefield.
Elemental Mastery and Born to Drive attached to Devoted Druid. Devoted Druid does not have summoning sickness, and has a power of one or greater.

   Steps

How does this combo work?
1
Activate Devoted Druid by tapping it, creating at least one 1/1 Elemental creature token with haste.
2
Activate Devoted Druid by putting a -1/-1 counter on it, untapping it.
3
Repeat.
4
If Devoted Druid has a power of two or greater, Devoted Druid becomes infinitely large, which allows you to use its mana ability instead to get infinite .

   Results

What do I get from this combo?
Infinite creature tokens with haste
Infinite ETB
Infinite green mana
Infinitely large Devoted Druid