Splinter Twin + Possessed Skaab + Time Walk

Splinter Twin

Possessed Skaab

Time Walk

How it works

1. Cast Time Walk getting an extra turn after this one.
2. Pass the turn.
3. Activate Possessed Skaab, by tapping it, creating a token copy of it with haste.
4. The token copy of Possessed Skaab enters the battlefield, returning Time Walk from your graveyard to your hand.
5. Repeat.