Scaretiller

Whenever Scaretiller becomes tapped, choose one —
• You may put a land card from your hand onto the battlefield tapped.
• Return target land card from your graveyard to the battlefield tapped.

Najeela, the Blade-Blossom

Whenever a Warrior attacks, you may have its controller create a 1/1 white Warrior creature token that's tapped and attacking.
{W}{U}{B}{R}{G}: Untap all attacking creatures. They gain trample, lifelink, and haste until end of turn. After this phase, there is an additional combat phase. Activate only during combat.

Rush of Knowledge

Draw cards equal to the highest mana value among permanents you control.

Scroll Rack

{1}, {T}: Exile any number of cards from your hand face down. Put that many cards from the top of your library into your hand. Then look at the exiled cards and put them on top of your library in any order.

Sakashima of a Thousand Faces

You may have Sakashima of a Thousand Faces enter as a copy of another creature you control, except it has Sakashima of a Thousand Faces's other abilities.
The "legend rule" doesn't apply to permanents you control.
Partner (You can have two commanders if both have partner.)

Eerie Ultimatum

Return any number of permanent cards with different names from your graveyard to the battlefield.

Irregular Cohort

Changeling (This card is every creature type.)
When Irregular Cohort enters, create a 2/2 colorless Shapeshifter creature token with changeling.

Shard Convergence

Search your library for a Plains card, an Island card, a Swamp card, and a Mountain card. Reveal those cards, put them into your hand, then shuffle.

Druids' Repository

Whenever a creature you control attacks, put a charge counter on Druids' Repository.
Remove a charge counter from Druids' Repository: Add one mana of any color.

Scarecrone

{1}, Sacrifice a Scarecrow: Draw a card.
{4}, {T}: Return target artifact creature card from your graveyard to the battlefield.

Padeem, Consul of Innovation

Artifacts you control have hexproof. (They can't be the targets of spells or abilities your opponents control.)
At the beginning of your upkeep, if you control the artifact with the highest mana value or tied for the highest mana value, draw a card.

Antler Skulkin

{2}: Target white creature gains persist until end of turn. (When it dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Scuttlemutt

{T}: Add one mana of any color.
{T}: Target creature becomes the color or colors of your choice until end of turn.

Changeling Titan

Changeling (This card is every creature type.)
Champion a creature (When this enters, sacrifice it unless you exile another creature you control. When this leaves the battlefield, that card returns to the battlefield.)