Scholar of Combustion

When this creature enters, exile up to one target instant or sorcery card from your graveyard. You may cast that card until the end of your next turn. (You still pay its costs. Timing rules still apply.)

Salvager of Secrets

When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Living Lightning

When this creature dies, return target instant or sorcery card from your graveyard to your hand.

Shameless Charlatan

Commander creatures you own have "{2}{U}: This creature becomes a copy of another target creature."

Mystic Peak

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {R}.

Pinnacle Monk

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Pinnacle Monk // Mystic Peak

Anarchist

When this creature enters, you may return target sorcery card from your graveyard to your hand.

Archaeomancer

Scholar of the Ages

When this creature enters, return up to two target instant and/or sorcery cards from your graveyard to your hand.

Scrivener

When this creature enters, you may return target instant card from your graveyard to your hand.

Mnemonic Wall

Defender
When this creature enters, you may return target instant or sorcery card from your graveyard to your hand.

Sivriss, Nightmare Speaker

{T}, Sacrifice another creature or an artifact: For each opponent, you mill a card, then return that card from your graveyard to your hand unless that player pays 3 life. (To mill a card, put the top card of your library into your graveyard.)
Choose a Background (You can have a Background as a second commander.)

Revolutionist

When this creature enters, return target instant or sorcery card from your graveyard to your hand.
Madness {3}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Shipwreck Dowser

Repository Skaab

Exploit (When this creature enters, you may sacrifice a creature.)
When this creature exploits a creature, return target instant or sorcery card from your graveyard to your hand.