msem-instigator

Poisonous 3 (Whenever this creature deals combat damage to a player, that player gets three poison counters.)
At the beginning of your upkeep, if an opponent is poisoned, you may have Mautakesh Strangler fight target creature you don't control.

When Maven of Fear enters, mill two cards.
Maven of Fear gets +2/+1 and has menace as long as six or more cards are in your graveyard.

Flying
Whenever you cast a spell, draw a card, then put a +1/+1 counter on Maven of Perspective.

As long as you control another white creature, Mavisa's Familar has lifelink. The same is true for blue and flying, black and deathtouch, and red and trample.

[+1]: Untap up to two target creatures and/or lands.
[–2]: Choose a color. Draw cards equal to the number of creatures you control of the chosen color.
[–7]: Reveal the top ten cards of your library. Put all creature and land cards revealed this way onto the battlefield and the rest into your hand.

Trample, hexproof
When Maw of a Thousand Worlds enters, distribute X +1/+1 counters among creatures you control, where X is the number of differently named lands you control.
When Maw of a Thousand Worlds dies, you may remove any number of counters from among permanents you control. For each counter removed this way, draw a card.

Destroy target non-Elf creature. Its controller loses 1 life for each Elf you control.

Menace
Landfall — Whenever a land you control enters, Mawdryk's Elite gets +1/+0 and gains deathtouch until end of turn.

Reach
When Mawdryk's Harrier enters, look at the top six cards of your library. You may put an Elf card with lesser mana value from among them onto the battlefield. Put the rest on the bottom of your library in a random order.
Other Elves you control get +1/+1.

Landfall — Whenever a land you control enters, add {G}.
{3}{G}: Target creature you control gets +2/+2 until end of turn.

Whenever Mawdryk, Endrison Warden or another nontoken Elf creature you control enters, create a 1/1 green Elf Druid creature token.
{B}{G}, Sacrifice two Elves: Destroy target non-Elf creature.

When you cast this spell from anywhere other than your hand, it deals 5 damage to any target.
Trample

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
Recursive — As long as Mayar, Nullcrowned is a Curse, they have all nonrecursive abilities of other Curses and creatures with breach you control.
Pay 3 life: Target enchantment creature gains haste and menace until end of turn.

This spell can't be countered.
Flying, haste
Mayu, the Endless Flow gets +2/+2 for each spell you've cast this turn.

Alpha (You may have this creature enter with a +1/+1 counter on it. If you do, it becomes alpha and can only attack alone.)

When Meadow Songstress enters, conjure three cards named Meadow Songstress and shuffle them into your main library.
Whenever a nontoken creature you control enters, if it shares a name with one or more other creatures you control, draw a card.

Enchant creature you control
Whenever enchanted creature attacks, mill three cards.
When enchanted creature leaves the battlefield, create an X/X green Spirit creature token, where X is equal to the number of card types among cards in your graveyard.

Gain control of target creature with power X or less.

Meandering Path enters tapped unless you control one or fewer other lands.
{T}: Add {R} or {G}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Shuffle the cards from your hand into your library, then draw that many cards.
Draw a card.

Enchant creature
You control enchanted creature.

Indestructible (Damage and effects that say “destroy” don't destroy this creature.)

When Mechanical Mastodon enters, you may return another target permanent you control to its owner's hand.

Deploy 4 (As this enters, you may tap any number of other creatures you control with total power 4 or more.)
When Mechanical Tactician enters deployed, tap up to two target creatures an opponent controls. Those creatures don't untap during their controller's next untap step.

Mechanized Ideal gets +X/+Y, where X is the highest base power among other creatures you control and Y is the highest base toughness among other creatures you control.