Changeling Titan, Changeling Hero, and Lumbering Battlement

Prerequisites

• Changeling Titan in hand or on the battlefield or in exile
• Changeling Hero in hand or on the battlefield or in exile
• Lumbering Battlement in hand or on the battlefield or in exile
• plus the mana cost of the creature in your hand available

Steps

1. Cast Changeling Titan for its mana cost
2. When Changeling Titan enters, it exiles Changeling Hero until Changeling Titan leaves the battlefield
3. Resolve any additional effects of Changeling Titan's ETB
4. When Changeling Hero leaves the battlefield, Lumbering Battlement is returned from exile to the battlefield
5. When Lumbering Battlement enters, it exiles Changeling Titan until Lumbering Battlement leaves the battlefield
6. Resolve any additional effects of Lumbering Battlement's ETB
7. When Changeling Titan leaves the battlefield, Changeling Hero is returned from exile to the battlefield
8. When Changeling Hero enters, it exiles Lumbering Battlement until Changeling Hero leaves the battlefield
9. Resolve any additional effects of Changeling Hero's ETB
10. When Lumbering Battlement leaves the battlefield, Changeling Titan is returned from exile to the battlefield
11. Repeat from step 2

Results

• Infinite creature ETB
• Infinite creature LTB