Hexavus, and Devoted Druid

Prerequisites

• Hexavus on the battlefield
• Devoted Druid on the battlefield
• Devoted Druid does not have summoning sickness

Steps

1. Activate Devoted Druid's first ability by tapping it, adding
2. Activate Devoted Druid's second ability by putting a -1/-1 counter on it, untapping it
3. Activate Hexavus' second ability by paying and removing the -1/-1 counter from Devoted Druid, putting a +1/+1 counter on Hexavus
4. Repeat

Results

• Infinite +1/+1 counters on Hexavus