msem-instigator

{T}: Add one mana of any color. Spend this mana only to cast a creature spell or activate an ability of a creature.
{5}{W}{U}{B}{R}{G}, Sacrifice Osk, the Maker's Pet: Create Osk Awakened, a legendary 20/20 green Squirrel God creature token with hexproof, trample, and indestructible.

({T}: Add {G}.)
Wanderlust — Otherworldly Forest enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

Reveal the top four cards of your library. You may put a creature or land card from among them into your hand. Put the rest into your graveyard.

({T}: Add {U}.)
Wanderlust — Otherworldly Island enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

({T}: Add {R}.)
Wanderlust — Otherworldly Mountain enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

({T}: Add {W}.)
Wanderlust — Otherworldly Plains enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

({T}: Add {B}.)
Wanderlust — Otherworldly Swamp enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

Manifest the top card of your library and the bottom card of your library. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Out-of-Depth Amateur can't attack or block alone.
Attain {4}{R} ({4}{R}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Outfitted Ibex has menace as long as it's embattled. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

Outlands Bodyguard can't attack alone.
You may exert Outlands Bodyguard as it attacks. When you do, it must be blocked this turn if able. (An exerted creature won't untap during your next untap step.)

When Over the Horizon enters, scry 1.
{T}: Add {C}.
{1}, {T}: Return Over the Horizon to its owner's hand.

Hexproof
When Overburdened Trader enters, create three 1/1 colorless Construct artifact creature tokens.

Whenever you cast an instant or sorcery spell, copy it. You may choose new targets for the copy. Overclock deals X damage to you, where X is the number of spells you've cast this turn.

Kicker—Sacrifice an artifact or creature. (You may sacrifice an artifact or creature in addition to any other costs as you cast this spell.)
Choose target creature you control. Put a +1/+1 counter on it if this spell was kicked. Then it deals damage equal to its power to target creature you don't control.

Target creature gets +2/+1 and gains haste until end of turn.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

{G}, Tap an untapped Nymph you control: Overgrown Beast gets +2/+2 until end of turn.

Overgrown Enclave enters tapped.
{T}: Add {G} or {U}.
{4}{G}{U}: Until end of turn, Overgrown Enclave becomes a Turtle creature with ward {2} in addition to its other types.
Scavenge {5}{G}{U}

{T}, Pay 1 life: Add {G} or {W}.
{1}, {T}, Sacrifice Overgrown Refuge: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Overgrown Ruins enters tapped.
As Overgrown Ruins enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Overgrown Siren must be blocked if able.

Trample
Overgrown Spellroot gets +1/+1 for each creature token you control.
When Overgrown Spellroot enters, create four 1/1 black Worm creature tokens.

Whenever Overgrowth Host attacks, germinate. Then creatures you control that are Saprolings or have counters on them gain trample until end of turn.
Saprolings you control get +1/+1.

This spell can't be countered.
Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Haste (This creature can attack and {T} as soon as it comes under your control.)