Hallar, the Firefletcher + Phyrexian Devourer + Slippery Bogbonder

Hallar, the Firefletcher

Phyrexian Devourer

Slippery Bogbonder

How it works

1. Activate Phyrexian Devourer by paying 0, exling the top card of your library and putting a number of +1/+1 counters on Phyrexian Devourer equal to that card's mana value.
2. If Phyrexian Devourer's power becomes seven or greater this way, it triggers.
3. Holding priority, repeat from step 1 until you have an empty library.
4. With the Phyrexian Devourer triggers on the stack, cast Slippery Bogbonder by paying 3.
5. When Slippery Bogbonder enters the battlefield, it triggers, moving all +1/+1 counters from Phyrexian Devourer onto Hallar.
6. Resolve all Phyrexian Devourer triggers from step 2, causing you to sacrifice it.
7. Cast any kicker or multikicker spell with kicker by paying its mana cost plus its kicker cost.
8. Hallar triggers, putting a +1/+1 counter on itself, then dealing damage equal to the number of +1/+1 counters on it to each opponent.

This explosive combination turns Phyrexian Devourer into a massive engine by repeatedly activating its ability to exile your entire library and pile up a mountain of +1/+1 counters, dodging its self-sacrifice trigger by holding priority. Before those lethal power-check triggers can resolve, you flash in Slippery Bogbonder to safely harvest all of those accumulated counters and shift them entirely onto Hallar, the Firefletcher. Finally, casting any kicked spell triggers Hallar's ability to unleash a devastating wave of damage directly to each opponent, scaled by the colossal number of counters you just transferred.