Springheart Nantuko + Overlord of the Hauntwoods + Spelunking + Mana Reflection

Springheart Nantuko

Overlord of the Hauntwoods

Spelunking

Mana Reflection

How it works

1. Declare Overlord of the Hauntwoods as an attacker.
2. Overlord of the Hauntwoods triggers, creating an untapped Everywhere land token due to Spelunking.
3. When the Everywhere token enters the battlefield, Springheart Nantuko triggers.
4. Holding priority, activate Everywhere by tapping it, adding .
5. Resolve the Springheart Nantuko trigger, causing you to pay 1 to create a token copy of Overlord of the Hauntwoods.
6. When the Overlord of the Hauntwoods token enters the battlefield, it triggers, creating a tapped Everywhere land token.
7. Repeat from step 3.

This loop transforms a single attack by Overlord of the Hauntwoods into an overwhelming army by exploiting the way lands enter the battlefield. When the Overlord attacks, it creates a land token named Everywhere, but thanks to Spelunking, that token enters the battlefield untapped instead of tapped. That landfall event triggers Springheart Nantuko, letting you tap the new Everywhere land in response for double the green mana due to Mana Reflection's replacement effect. You then use that generated mana to pay for Springheart Nantuko's landfall cost, creating a token copy of Overlord of the Hauntwoods that immediately enters to spawn another Everywhere token and restart the chain.