Doom's Time Platform + Rift Elemental + Temporal Manipulation

Prerequisites

• You control a creature that can attack and that cannot be blocked or killed by an opponent.

Steps

1. 1Cast Temporal Manipulation by paying its mana cost, causing you to take an extra turn after this one.
2. 2Declare any creature as an attacker. When you do, Doom's Time Platform triggers, exiling Temporal Manipulation from your graveyard with two time counters on it.
3. 3Move to your next turn. At the beginning of your upkeep, Temporal Manipulation's suspend ability triggers, removing a time counter from it.
4. 4Activate Rift Elemental by paying and removing a time counter from Temporal Manipulation.
5. 5Temporal Manipulation's suspend ability triggers, causing you to cast it without paying its mana cost.
6. 6Resolve Temporal Manipulation, causing you to take an extra turn after this one.
7. 7Repeat from step 2.

Effects

• Infinite turns
• Lock