Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Toothy, Imaginary Friend

Partner with Pir, Imaginative Rascal (When this creature enters, target player may put Pir into their hand from their library, then shuffle.)
Whenever you draw a card, put a +1/+1 counter on Toothy, Imaginary Friend.
When Toothy leaves the battlefield, draw a card for each +1/+1 counter on it.

Wrath of God

Destroy all creatures. They can't be regenerated.

Wall of Souls

Defender (This creature can't attack.)
Whenever Wall of Souls is dealt combat damage, it deals that much damage to target opponent or planeswalker.