msem-instigator

Target creature you control gets +3/+3 until end of turn. Then if that creature has power 10 or greater, each other creature you control gets +3/+3 until end of turn.

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{6}: Unlock Ancient Maze. If the revealed card is green, put it into your hand. Otherwise, put it on top of your library.

Ward {3}

When Ancient of the Glade enters, put a +1/+1 counter on each other creature you control.
{2}, Remove a +1/+1 counter from a creature you control: That creature gains indestructible until end of turn.

Reach
Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
When Angelbane Spider enters, destroy target creature with flying.

{T}, Reveal an Angel card from your hand: For each of that card's colors, add one mana of that color.

Whenever Angeltouched Dryad or another permanent you control is turned face up, add {C}{C}.
Morph {2} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

{T}: Add {G}.
{G}, {T}: Target creature gains trample until end of turn.

Whenever another nontoken creature you control enters, create a 1/1 green Saproling creature token.
{1}{G}, {T}: Populate. (Create a token that's a copy of a creature token you control.)

Reach, trample
When Anran, Root Steward enters, destroy up to three target noncreature permanents. For each permanent destroyed this way, its controller creates a colorless enchantment land token named Paradise with hexproof and “{T}: Add one mana of any color.”

Vigilance, trample
Whenever another Horror you control enters, choose one —
• Destroy target artifact or enchantment.
• You gain 4 life.
• Apex Abomination fights another target creature.

At the beginning of your upkeep, if an opponent controls more creatures than you, you may reveal the top seven cards of your library. Target opponent chooses a creature card revealed this way. Put that card onto the battlefield, and the rest into your graveyard.

Target creature you control deals damage equal to its power to target creature or planeswalker you don't control.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)

When Apprentice Summoner enters, search your library for a creature card with mana value 1 or less, put it onto the battlefield, then shuffle.

Target creature you control deals damage equal to its power to target creature you don't control.

This spell costs {1} less to cast for each differently named land you control.
Reach, trample

Trample
When Arborback Stomper enters, you gain 5 life.

Reach
When Archived Intelligence enters, surveil 2. Then if you control a token, draw a card.

Flying, trample

Create three 2/2 green Wolf creature tokens.

Archive 5 (As this enters, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
You may play lands from the archived library.

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature gets +2/+2.
{1}{G}: Regenerate enchanted creature.

Reach, vigilance

{T}: Add {G}.
{1}{G}, {T}: Return target land card from your graveyard to the battlefield tapped.