Gyre Sage

Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
{T}: Add {G} for each +1/+1 counter on Gyre Sage.

Ancestral Statue

When Ancestral Statue enters, return a nonland permanent you control to its owner's hand.

Damning Verdict

Destroy all creatures with no counters on them.

Cathars' Crusade

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Hamza, Guardian of Arashin

This spell costs {1} less to cast for each creature you control with a +1/+1 counter on it.
Creature spells you cast cost {1} less to cast for each creature you control with a +1/+1 counter on it.

Copper Myr

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Sol Ring

Armageddon

Rishkar, Peema Renegade

When Rishkar, Peema Renegade enters, put a +1/+1 counter on each of up to two target creatures.
Each creature you control with a counter on it has "{T}: Add {G}."

Gold Myr

Altar of Bone

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a creature card, reveal it, put it into your hand, then shuffle.

Myr Welder

Imprint — {T}: Exile target artifact card from a graveyard.
Myr Welder has all activated abilities of all cards exiled with it.

Eladamri's Call

Search your library for a creature card, reveal that card, put it into your hand, then shuffle.

Kalonian Hydra

Trample
Kalonian Hydra enters with four +1/+1 counters on it.
Whenever Kalonian Hydra attacks, double the number of +1/+1 counters on each creature you control.