Slime Rancher

When Slime Rancher deals combat damage to
a creature, if she dealt half or less of that creatures toughness, you may take control of that creature. That creature has: "At the beginning of the upkeep roll a d20:
1-9: This cards owner takes control of it.
10-19: Put a +1/+1 counter on this creature.
20: This creature no longer has this beginning of upkeep trigger"