Tyvar, the Pummeler, and Devoted Druid

Prerequisites

• Tyvar, the Pummeler on the battlefield
• Devoted Druid on the battlefield
• available

Steps

1. Activate Devoted Druid's first ability by tapping it, adding
2. Activate Tyvar by paying , giving creatures you control at least +3/+3 until end of turn
3. Activate Devoted Druid's second ability by putting a -1/-1 counter on it, untapping it
4. Activate Devoted Druid's first ability by tapping it, adding
5. Repeat from step 3 until Devoted Druid is tapped and has exactly 1 toughness
6. Repeat from step 1, increasing the +X/+X effect in step 1 each time

Results

• Infinite green mana
• Infinitely large creatures you control until end of turn