Pentavus + Necrosynthesis + Phyrexian Altar

Pentavus

Necrosynthesis

Phyrexian Altar

How it works

1. Activate Pentavus' first ability by paying 1 and removing a +1/+1 counter from it, creating a 1/1 Pentavite creature token.
2. Activate Phyrexian Altar by sacrificing the Pentavite, adding 1.
3. The Pentavite dies, triggering Pentavus, putting a +1/+1 counter on itself.
4. Repeat.

This clever loop is centered around Pentavus, which acts as both the engine and the fuel by constantly converting its own internal counters into token children. Phyrexian Altar provides the crucial sacrifice outlet that converts each newly hatched Pentavite into mana, which in turn pays to activate Pentavus all over again. Meanwhile, Necrosynthesis supercharges the enchanted Pentavus by capitalizing on all those dying tokens, packing its power with extra counters while standing ready to dig deep into your library if the creature ever finally perishes.