Time Sieve + Encroaching Mycosynth + Delina, Wild Mage + Lena, Selfless Champion

Time Sieve

Encroaching Mycosynth

Delina, Wild Mage

Lena, Selfless Champion

How it works

1. Declare Delina as an attacker.
2. Delina triggers, creating at least one nonlegendary token copy of Lena with haste.
3. When the Lena token enters the battlefield, it triggers, creating at least four 1/1 Soldier creature tokens.
4. Activate Time Sieve by tapping it, sacrificing the Lena token and the Soldier tokens, causing you to take an extra turn after this one.
5. Repeat each turn.