Koll, the Forgemaster, Phyrexian Altar, Obsidian Battle-Axe, and Grim Initiate

Prerequisites

• Koll, the Forgemaster on the battlefield
• Phyrexian Altar on the battlefield
• Obsidian Battle-Axe on the battlefield
• Grim Initiate in hand
• available

Steps

1. Cast Grim Initiate by paying
2. Grim Initiate enters the battlefield, triggering Obsidian Battle-Axe, attaching it to Grim Initiate
3. Activate Phyrexian Altar by sacrificing Grim Initiate, adding
4. Grim Initiate dies, triggering itself and Koll
5. Resolve Grim Initiate's trigger, amassing 1
6. Resolve Koll's trigger, returning Grim Initiate from your graveyard to your hand
7. Activate Phyrexian Altar by sacrificing the Zombie Army token, adding one mana of any color
8. Repeat
9. Once you have infinite mana, you may repeat the loop without sacrificing the Zombie Army token

Results

• Infinite colored mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinitely large Zombie Army
• Infinite sacrifice triggers
• Infinite storm count