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.

Thoughtcast

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Draw two cards.

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

This spell costs {1} less to cast if you control a creature with flying.
Draw two cards.

Draw a card. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.