You may activate loyalty abilities of Teferi, Master of Time on any player's turn any time you could cast an instant.
[+1]: Draw a card, then discard a card.
[−3]: Target creature you don't control phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)
[−10]: Take two extra turns after this one.

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
At the beginning of each upkeep, create a 1/1 green Saproling creature token.
Saprolings you control get +2/+2 as long as you have the city's blessing.

Enchant creature with converted mana cost 2 or less
You control enchanted creature.

Haste
Whenever Thunderkin Awakener attacks, choose target Elemental creature card in your graveyard with toughness less than Thunderkin Awakener's toughness. Return that card to the battlefield tapped and attacking. Sacrifice it at the beginning of the next end step.

When Tibalt's Rager dies, it deals 1 damage to any target.
: Tibalt's Rager gets +2/+0 until end of turn.

Kicker (You may pay an additional as you cast this spell.)
Vigilance, trample
If Untamed Kavu was kicked, it enters the battlefield with three +1/+1 counters on it.

[+1]: Distribute two +1/+1 counters among up to two target creatures. They gain trample until end of turn.
[−3]: Target creature you control deals damage equal to its power to target creature or planeswalker.
[−5]: You may reveal a creature card you own from outside the game and put it into your hand.

Escape—, Exile four other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Voracious Typhon escapes with three +1/+1 counters on it.

Destroy target creature. You gain life equal to its toughness. You may search your library and/or graveyard for a card named Vraska, Regal Gorgon, reveal it, and put it into your hand. If you search your library this way, shuffle it.

Afflict 4 (Whenever this creature becomes blocked, defending player loses 4 life.)
Whenever Wildfire Eternal attacks and isn't blocked, you may cast an instant or sorcery spell from your hand without paying its mana cost.

Whenever you cast a Knight spell, create a 1/1 white Human creature token.

Commander ninjutsu (, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand or the command zone tapped and attacking.)
Whenever a Ninja you control deals combat damage to a player, reveal the top card of your library and put that card into your hand. Each opponent loses life equal to that card's converted mana cost.

Partner with Okaun, Eye of Chaos (When this creature enters the battlefield, target player may put Okaun into their hand from their library, then shuffle.)
At the beginning of combat on your turn, flip a coin until you lose a flip.
Whenever a player wins a coin flip, draw a card.