Sakashima's Student, and Felidar Guardian

Prerequisites

• Sakashima's Student in hand
• Felidar Guardian on the battlefield

Steps

1. Cast Sakashima's Student by paying its mana cost, choosing to have it enter the battlefield as a copy of Felidar Guardian When Sakashima's Student enters the battlefield, it triggers, blinking Felidar Guardian
2. When Felidar Guardian enters the battlefield, it triggers, blinking Sakashima's Student
3. Choose to have Sakashima's Student enter the battlefield as a copy of Felidar Guardian
4. Repeat from step 2

Results

• Infinite LTB
• Infinite ETB