Experiment Kraj, Devoted Druid, and Hardened Scales

Prerequisites

• Experiment Kraj on the battlefield
• Devoted Druid on the battlefield
• Hardened Scales on the battlefield
• Experiment Kraj does not have summoning sickness

Steps

1. Activate Experiment Kraj by tapping it, putting two +1/+1 counters onto Devoted Druid
2. Activate Experiment Kraj using Devoted Druid's last ability by putting a -1/-1 counter on itself, untapping it
3. Activate Experiment Kraj's own ability, putting two +1/+1 counters on itself
4. Remove the -1/-1 counter and one of the +1/+1 counters from Experiment Kraj as a state-based action
5. Repeat steps 2 through 4 any number of times, resulting in any number of +1/+1 counters on Experiment Kraj
6. Activate Experiment Kraj using Devoted Druid's last ability by putting a -1/-1 counter on itself, untapping it
7. Activate Experiment Kraj using Devoted Druid's first ability by tapping it, add
8. Repeat steps 6 and 7 any number of times
9. You may also activate Experiment Kraj's own ability any number of times instead of step 7, putting any number of +1/+1 counters onto creatures

Results

• Infinite +1/+1 counters
• Infinite green mana