Chaos Spewer + Mikaeus, the Unhallowed + Phyrexian Altar

BR identity

Commander legal

The 3 combo pieces

• Chaos Spewer
• Mikaeus, the Unhallowed
• Phyrexian Altar

How to execute it

1. Activate Phyrexian Altar by sacrificing Chaos Spewer.
2. When Chaos Spewer dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
3. When Chaos Spewer enters the battlefield, it triggers, putting a -1/-1 counter on it.
4. Repeat.

What the combo produces

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