Jace, Cunning Castaway + Resourceful Defense + Cloudstone Curio Combo

All permanents on the battlefield.

Jace has at least five loyalty counters on it.

Activate Jace's third loyalty ability by removing five loyalty counters from it, creating two token copies of Jace that aren't legendary.

When the Jace tokens enter the battlefield, Cloudstone Curio triggers twice.

Resolve the first trigger, choosing to return nothing to your hand.

Resolve the second trigger, returning a Jace token from the battlefield to your hand.

When the Jace token leaves the battlefield, Resourceful Defense triggers, putting three loyalty counters on the remaining Jace token.

Repeat using the Jace token.

Infinite copies of a specific planeswalker