Initial Card State
- Mardu Siegebreaker on the battlefield (without summoning sickness).
- Felidar Guardian in exile.
Steps
- Declare Mardu Siegebreaker as an attacker, triggering its second ability, creating at least one token copy of Felidar Guardian that is tapped and attacking.
- When the Felidar Guardian token(s) enter the battlefield, they trigger.
- Resolve the first trigger, blinking Mardu Siegebreaker.
- Mardu Siegebreaker leaves and enters the battlefield, causing the nontoken Felidar Guardian to return to the battlefield from exile, and triggering Felidar Guardian and Mardu Siegebreaker's first ability.
- Resolve the Mardu Siegebreaker trigger, exiling the nontoken Felidar Guardian until Mardu Siegebreaker leaves the battlefield.
- Resolve the Felidar Guardian trigger, blinking Mardu Siegebreaker.
- Repeat from step 4.
Results
- Infinite LTB.
- Infinite ETB.
Bracket Tag
This combo has been estimated to be Exhibition (Bracket 1+).