Ayula, Queen Among Bears, Sekki, Seasons' Guide, and Arcane Adaptation

Prerequisites

• Ayula, Queen Among Bears on the battlefield
• Sekki, Seasons' Guide in hand
• Arcane Adaptation on the battlefield
• Sekki has at least eight +1/+1 counters on it

Steps

1. Cause a creature to enter the battlefield, which is a Bear due to Arcane Adaptation
2. Ayula triggers, causing Sekki to fight a creature you don't control
3. Sekki removes a number of +1/+1 counters from it equal to the damage it would've been dealt and creates that many 1/1 Spirit creature tokens, which are Bears due to Arcane Adaptation
4. When the Spirit Bear(s) enter the battlefield, Ayula triggers that many times
5. If Sekki is on the battlefield, resolve an Ayla trigger, causing Sekki to fight a creature you don't control, and then repeat from step 3
6. If Sekki is not on the battlefield, activate Sekki by sacrificing eight Spirits, returning it from your graveyard to the battlefield as a Bear with eight +1/+1 counters on it due to Arcane Adaptation
7. If Sekki entered the battlefield, Ayula triggers, causing Sekki to fight a creature you don't control
8. Repeat from step 3

Results

• Destroy all creatures opponents control whenever a creature enters the battlefield under your control