Rin and Seri, Inseparable

Whenever you cast a Dog spell, create a 1/1 green Cat creature token.
Whenever you cast a Cat spell, create a 1/1 white Dog creature token.
{R}{G}{W}, {T}: Rin and Seri, Inseparable deals damage to any target equal to the number of Dogs you control. You gain life equal to the number of Cats you control.

Elder Druid

{3}{G}, {T}: You may tap or untap target artifact, creature, or land.

Emerald Charm

Choose one —
• Untap target permanent.
• Destroy target non-Aura enchantment.
• Target creature loses flying until end of turn.

Jandor's Saddlebags

Awakening

At the beginning of each upkeep, untap all creatures and lands.

Nissa, Genesis Mage

+2: Untap up to two target creatures and up to two target lands.
−3: Target creature gets +5/+5 until end of turn.
−10: Look at the top ten cards of your library. You may put any number of creature and/or land cards from among them onto the battlefield. Put the rest on the bottom of your library in a random order.

Fyndhorn Brownie

Elmar, Ulvenwald Informant

Haste
Whenever you cast your second spell each turn, untap target creature, then investigate. (Create a colorless Clue artifact token with "{2}, Sacrifice this artifact: Draw a card.")
Friends forever (You can have two commanders if both have friends forever.)

Halo Fountain

{W}, {T}, Untap a tapped creature you control: Create a 1/1 green and white Citizen creature token.
{W}{W}, {T}, Untap two tapped creatures you control: Draw a card.
{W}{W}{W}{W}{W}, {T}, Untap fifteen tapped creatures you control: You win the game.

Malachite Talisman

Whenever a player casts a green spell, you may pay {3}. If you do, untap target permanent.

Nacre Talisman

Whenever a player casts a white spell, you may pay {3}. If you do, untap target permanent.

Hematite Talisman

Whenever a player casts a red spell, you may pay {3}. If you do, untap target permanent.

Magewright's Stone

{1}, {T}: Untap target creature that has an activated ability with {T} in its cost.

Astral Cornucopia

Astral Cornucopia enters the battlefield with X charge counters on it.
{T}: Choose a color. Add one mana of that color for each charge counter on Astral Cornucopia.