Choose a creature card name. Search target opponent's graveyard, hand, and library for any number of cards with that name and exile them. Then that player shuffles their library...
Morph {B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
Whenever another nontoken creature you control dies, draw a card...
Search your library for a card and put that card into your hand. Then shuffle your library.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, add {B}{B}{B}...
Deathtouch
Exploit (When this creature enters the battlefield, you may sacrifice a creature.)
When Sidisi, Undead Vizier exploits a creature, you may search your library for a card, put it into your hand, then shuffle your library...
Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
{2}{G/U}{G/U}: Put the top two cards of your library into your graveyard, then return a nonland card of an opponent's choice from your graveyard to your hand...
Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change its text by replacing all instances of "target" with "each.")..
Instant and sorcery spells you cast cost {1} less to cast.
Whenever a spell or ability you control counters a spell, you may draw a card. If you do, discard a card...