Yannik, Scavenging Sentinel, Fiend Hunter, and Changeling Titan

Prerequisites

• Yannik, Scavenging Sentinel in hand or on the battlefield or in exile
• Fiend Hunter in hand or on the battlefield or in exile
• Changeling Titan in hand or on the battlefield or in exile
• plus the mana cost of the creature in your hand available

Steps

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

Results

• Infinite +1/+1 counters on creatures you control
• Infinite creature ETB
• Infinite creature LTB