Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Ink-Eyes, Servant of Oni

Ninjutsu {3}{B}{B} ({3}{B}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Ink-Eyes, Servant of Oni deals combat damage to a player, you may put target creature card from that player's graveyard onto the battlefield under your control.
{1}{B}: Regenerate Ink-Eyes.

Sakiko, Mother of Summer

Whenever a creature you control deals combat damage to a player, add that much {G}. Until end of turn, you don't lose this mana as steps and phases end.

Sphinx Ambassador

Flying
Whenever Sphinx Ambassador deals combat damage to a player, search that player's library for a card, then that player chooses a card name. If you searched for a creature card that doesn't have that name, you may put it onto the battlefield under your control. Then that player shuffles.

Sharuum the Hegemon

Flying
When Sharuum the Hegemon enters, you may return target artifact card from your graveyard to the battlefield.

Kemba, Kha Regent

At the beginning of your upkeep, create a 2/2 white Cat creature token for each Equipment attached to Kemba, Kha Regent.

Reversal of Fortune

Target opponent reveals their hand. You may copy an instant or sorcery card in it. If you do, you may cast the copy without paying its mana cost.

Sharding Sphinx

Flying
Whenever an artifact creature you control deals combat damage to a player, you may create a 1/1 blue Thopter artifact creature token with flying.