Prototype Portal, Dross Scorpion, Ravenous Intruder, and Cathodion

Prerequisites

• Prototype Portal on the battlefield
• Dross Scorpion on the battlefield
• Ravenous Intruder on the battlefield
• Cathodion on the battlefield
• undefined available

Steps

1. Activate Prototype Portal by paying and tapping it, creating a token copy of Cathodion
2. Activate Ravenous Intruder by sacrificing Cathodion
3. When Cathodion dies, Cathodion and Dross Scorpion trigger
4. Resolve the Cathodion trigger, adding
5. Resolve the Dross Scorpion trigger, untapping Prototype Portal
6. Resolve the Ravenous Intruder ability, giving it +2/+2 until end of turn
7. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Infinitely large Ravenous Intruder until end of turn