Dread Slaver, Flayer of the Hatebound, Mikaeus, the Unhallowed, and Phyrexian Altar

Prerequisites

• Dread Slaver on the battlefield
• Flayer of the Hatebound on the battlefield
• Mikaeus, the Unhallowed on the battlefield
• Phyrexian Altar on the battlefield

Steps

1. Activate Phyrexian Altar by sacrificing Dread Slaver, adding one mana of any color
2. When Dread Slaver dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it
3. When Dread Slaver enters the battlefield, Flayer of the Hatebound triggers, causing Dread Slaver to deal damage to itself equal to its power
4. Activate Phyrexian Altar by sacrificing Dread Slaver, adding one mana of any color
5. Dread Slaver triggers, returning itself from your graveyard to the battlefield
6. Repeat from step 3

Results

• Infinite colored mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers