Heartless Hidetsugu, Collective Inferno, and Gideon's Sacrifice

Prerequisites

• Heartless Hidetsugu on the battlefield
• Collective Inferno on the battlefield
• Gideon's Sacrifice in hand
• available

Steps

1. Cast Gideon's Sacrifice by paying
2. Activate Heartless Hidetsugu by tapping it, dealing damage to each opponent equal to half their life total, rounded down, times 2, and dealing no damage to you due to Gideon's Sacrifice

Results

• Near-infinite damage