Lotus Ring + Puresteel Paladin + Marneus Calgar + Fires of Yavimaya

Lotus Ring

Puresteel Paladin

Marneus Calgar

Fires of Yavimaya

How it works

1. Activate Marneus Calgar by paying 6, creating two 2/2 Astartes Warrior creature tokens.
2. When the Astartes Warriors enter the battlefield, Marneus Calgar triggers, causing you to draw a card.
3. Activate Lotus Ring's equip ability by paying 0 due to Puresteel Paladin, attaching it to an Astartes Warrior.
4. Activate the Astartes Warrior with Lotus Ring attached by tapping and sacrificing it, adding 3.
5. Repeat from step 3 for the remaining Astartes Warrior.
6. Repeat from step 1.

This engine uses Marneus Calgar's activated ability to continuously churn out Astartes Warrior tokens, which immediately trigger his own card-drawing prowess. Puresteel Paladin provides the critical engine-greasing, lowering Lotus Ring's equip cost to zero so you can freely snap the equipment onto each new token without spending precious mana. Once equipped, Lotus Ring lets you sacrifice the token for three mana to help fund the next activation of Marneus Calgar, while Fires of Yavimaya grants your forces the haste they need to tap right away if required, though the true genius here lies in feeding the loop entirely off Marneus Calgar's token generation and Puresteel Paladin's cost-reduction.