Mordenkainen

Body of Knowledge's power and toughness are each equal to the number of cards in your hand.

You have no maximum hand size.

Whenever this creature is dealt damage, draw that many cards.

Tishana's power and toughness are each equal to the number of cards in your hand.

You have no maximum hand size.

When Tishana enters, draw a card for each creature you control.

Enchant your library

Enchanted library is an artifact creature on the battlefield with power and toughness each equal to the number of cards in it. It's still a library.

If enchanted library would leave the battlefield, exile this Aura instead.

Reach

When Bonny Pall enters, create Beau, a legendary blue Ox creature token with "Beau's power and toughness are each equal to the number of lands you control."

Whenever you attack, draw a card, then you may put a land card from your hand or graveyard onto the battlefield.

+1: Create a 1/1 colorless Thopter artifact creature token with flying.

0: Draw a card. If you control three or more artifacts, draw two cards instead.

−9: You get an emblem with "At the beginning of your end step, search your library for a permanent card, put it onto the battlefield, then shuffle."

Whenever you draw a card, put a loyalty counter on Teferi.

0: Draw a card.

−2: Create a 2/2 blue Spirit creature token with vigilance and "Whenever you draw a card, put a +1/+1 counter on this token."

−12: Target opponent chooses a permanent they control and returns it to its owner's hand. Then they shuffle each nonland permanent they control into its owner's library.