Krark, the Thumbless, Irenicus's Vile Duplication, and Multiversal Incursion

Prerequisites

• Krark, the Thumbless on the battlefield
• Irenicus's Vile Duplication in hand
• Multiversal Incursion on the battlefield
• available

Steps

1. Cast Multiversal Incursion by paying its mana cost, targeting Krark
2. When you cast that spell, Krark and any additional copies of Krark trigger
3. Resolve all Krark triggers, copying that spell for each flip you won, and returning the original to your hand as long as you lost at least one flip
4. If you won every flip, resolve the card itself, creating one more Krark token and putting the card into your graveyard
5. If you need additional mana and the Mana Ritual is still in your hand, cast the Mana Ritual by paying its costs, then repeat from step 2
6. If you have sufficient mana and Multiversal Incursion is still in your hand, instead repeat from step 1
7. If you have sufficient mana and Multiversal Incursion is in your graveyard, instead cast Irenicus's Vile Duplication, then repeat from step 2
8. If you manage to pass a critical threshold of Krark copies before both copy spells ends up in your graveyard, this combo is overwhelmingly likely to be an infinite loop from that point on
9. See the widget below for failure chances
10. Once you have infinite mana and infinite copies of Krark, you can repeat this loop with any instant or sorcery you can cast

Results

• Infinite copies of creatures you control
• Infinite copies of instant or sorcery spells you cast
• Infinite magecraft triggers
• Infinite storm count