Yenna, Redtooth Regent, Second Wind, and Thaumatog

Prerequisites

• Yenna, Redtooth Regent on the battlefield
• Second Wind on the battlefield
• Thaumatog on the battlefield
• You control a creature that can tap to produce at least
• Yenna does not have summoning sickness

Steps

1. Activate the mana-producing creature by tapping it, adding at least
2. Activate Yenna by paying and tapping it, creating a token copy of Second Wind attached to the mana-producing creature, then untapping Yenna and causing you to scry 2
3. Activate the Second Wind token's second ability by tapping it, untapping the mana-producing creature
4. Activate Thaumatog's second ability by sacrificing the Second Wind token, causing Thaumatog to get +1/+1 until end of turn
5. Repeat

Results

• Infinitely large Thaumatog until end of turn
• Infinite scry 2