Mnemonic Wall + Erratic Portal + Time Warp

Mnemonic Wall

Erratic Portal

Time Warp

How it works

1. Cast Time Warp by paying 3, taking an extra turn after this one.
2. Cast Mnemonic Wall by paying 4.
3. Mnemonic Wall enters the battlefield, returning Time Warp from your graveyard to your hand.
4. Activate Erratic Portal by paying 1 and tapping it, returning Mnemonic Wall from the battlefield to your hand.
5. Repeat each turn.