msem-instigator

Trample
When Arpechian Yatte enters, put a +1/+1 counter on each other creature you control.
Whenever another creature you control enters, put a +1/+1 counter on Arpechian Yatte.

Basic Forests you control have “{G}, {T}: Untap target attacking creature and remove it from combat.”

When Bauble Collector enters, you may return another permanent you control to its owner's hand.

Concord — When Beetleback Forager enters, if there are four or more card types among permanents you control, return target card from your graveyard to your hand.

Trample
Whenever Belligerent's Augur or another Warrior you control deals combat damage to a player, you may pay {1}{U}. If you do, draw a card.

When Bessie's Brood enters, it fights target creature. (If there are no other creatures, it eats itself.)

{G}, {T}, Remove a +1/+1 counter from a creature you control: Create a 2/2 green Ox creature token.

At the beginning of your upkeep, you may discard a land card. When you do, create a 2/2 green Wolf creature token.

Reach
Menagerie — When Canopyctopus enters, if there are five or more creature types among creatures you control, reveal the top card of your library. If its mana value is less than or equal to the number of lands you control, draw a card. Otherwise, you may put that card into your graveyard.

Vigilance, reach
Whenever Cave Spider blocks a creature with flying, Cave Spider gets +2/+0 until end of turn.

When Chantwood Channeler enters from your graveyard, it gains haste and creatures you control get +3/+3 and gain trample until end of turn.
{5}{G}{G}{G}, Sacrifice a creature: Return Chantwood Channeler from your graveyard to the battlefield. Activate only as a sorcery.

Other Shaman creatures you control get +1/+0.
Revive {4}{G}{G} ({4}{G}{G}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
{1}{G}: Untap Chantwood Guards.

{1}{G}, Discard a card: Target land you control becomes a 3/3 Elemental creature. It's still a land. Exile the top card of your library face down.
Whenever a land creature you control deals combat damage to a player, put a card exiled with Children of Gos into your hand.

Trample
Whenever a lore counter is put on a Saga you control, Chimperial Guard gets +2/+2 until end of turn.

Trample
When Contentious Yak enters, another target creature you control gets +1/+1 and gains trample until end of turn.

Vigilance, trample
Whenever you draw your second card each turn, put a +1/+1 counter on Coralblade Cohort.
Cycling {G} ({G}, Discard this card: Draw a card.)

Reach
Improve {1}{G/W} ({1}{G/W}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on that creature instead.

When Cosmonaut Pioneer enters or leaves the battlefield, choose one—
• Scry 1, then draw a card.
• Create a 3/3 green Alien creature token with trample.
• You gain 5 life.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
{2}{G}: Crazed Sprareos gets +2/+2 until end of turn. Activate only once each turn.

Vigilance
Crinster Ranger enters with X +1/+1 counters on it, where X is the number of +1/+1 counters among other creatures you control.

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
Other creatures you control with distorted get +2/+2.

Trample
Dauntless Pathmaker can't be blocked by creatures with power 2 or less.

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)