Culling the Weak

As an additional cost to cast this spell, sacrifice a creature.
Add {B}{B}{B}{B}.

Archmage of Runes

Instant and sorcery spells you cast cost {1} less to cast.
Whenever you cast an instant or sorcery spell, draw a card.

Energy Tap

Tap target untapped creature you control. If you do, add an amount of {C} equal to that creature's mana value.

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Doctor Octopus, Master Planner

Other Villains you control get +2/+2.
Your maximum hand size is eight.
At the beginning of your end step, if you have fewer than eight cards in hand, draw cards equal to the difference.

Dark Petition

Search your library for a card, put that card into your hand, then shuffle.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, add {B}{B}{B}.

Cabal Ritual

Add {B}{B}{B}.
Threshold — Add {B}{B}{B}{B}{B} instead if there are seven or more cards in your graveyard.

Swamp

Fandaniel, Telophoroi Ascian

Whenever you cast an instant or sorcery spell, surveil 1.
At the beginning of your end step, each opponent may sacrifice a nontoken creature of their choice. Each opponent who doesn't loses 2 life for each instant and sorcery card in your graveyard.