Doom's Time Platform, Shivan Sand-Mage, Temporal Manipulation, and Thassa, Deep-Dwelling

Prerequisites

• Doom's Time Platform on the battlefield
• Shivan Sand-Mage on the battlefield
• Temporal Manipulation in the graveyard
• Thassa, Deep-Dwelling on the battlefield
• available

Steps

1. Declare any creature as an attacker
2. When you do, Doom's Time Platform triggers, exiling Temporal Manipulation from your graveyard with two time counters on it
3. Blink Shivan Sand-Mage using Thassa
4. When Shivan Sand-Mage enters, it triggers, removing two time counters from Temporal Manipulation
5. Temporal Manipulation's suspend ability triggers, causing you to cast it without paying its mana cost
6. Resolve Temporal Manipulation, causing you to take an extra turn after this one
7. Repeat each turn

Results

• Infinite turns
• Lock