Namor the Sub-Mariner + Phyrexian Altar + Mystic Speculation + Vadrik, Astral Archmage

Namor the Sub-Mariner

Phyrexian Altar

Mystic Speculation

Vadrik, Astral Archmage

How it works

1. Cast Mystic Speculation by paying due to Vadrik.
2. Namor triggers, creating a 1/1 Merfolk creature token.
3. Resolve Mystic Speculation.
4. Activate Phyrexian Altar by sacrificing the Merfolk, adding .
5. Repeat.

This loop turns the cost-reduction of Vadrik, Astral Archmage into an infinite spell-casting engine by reducing Mystic Speculation's mana cost down to just a single blue mana. Once cast, Namor the Sub-Mariner triggers to instantly reward you with a 1/1 blue Merfolk creature token for every blue mana symbol in the spell's cost. You then feed that newly spawned token right into Phyrexian Altar to generate the exact blue mana needed to cast Mystic Speculation again. Because Mystic Speculation's scry ability lets you constantly filter through your deck, you never run out of gas, fueling an endless cycle of sacrifices, casts, and triggers.