Add 1 counter -> Take 1 70/1/1 Skyreaper Drone Subordinate with "Whenever this unit attacks, put 1 captivity counter on the defending unit." and put it into any arena. Play only during your build step.
Remove 2 counters Tap a damaged unit with 2 or more captivity counters on it.
Remove 4 counters Put 1 damage counter on each unit with 1 or more captivity counters on it.