When Avenger of Zendikar enters the battlefield, create a 0/1 green Plant creature token for each land you control.

Landfall -- Whenever a land enters the battlefield under your control, you may put a +1/+1 counter on each Plant creature you control.

Creatures with power less than Champion of Lambholt's power can't block creatures you control.

Whenever another creature enters the battlefield under your control, put a +1/+1 counter on Champion of Lambholt.

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker.

When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)

When Coiling Oracle enters the battlefield, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.

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

Counter target spell.

Converge -- Crystalline Crawler enters the battlefield with a +1/+1 counter on it for each color of mana spent to cast it.

Remove a +1/+1 counter from Crystalline Crawler: Add one mana of any color.

{T}: Put a +1/+1 counter on Crystalline Crawler.

When Deepglow Skate enters the battlefield, double the number of each kind of counter on any number of target permanents.

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Landfall -- Whenever a land enters the battlefield under your control, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Whenever a creature with power 2 or less enters the battlefield under your control, you get an experience counter.

At the beginning of combat on your turn, put X +1/+1 counters on another target creature you control, where X is the number of experience counters you have.

Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Whenever a +1/+1 counter is put on Fathom Mage, you may draw a card.

Whenever a player casts a spell, you may put a +1/+1 counter on Forgotten Ancient.

At the beginning of your upkeep, you may move any number of +1/+1 counters from Forgotten Ancient onto other creatures.

Flash

When Frilled Mystic enters the battlefield, you may counter target spell.

{T}: Add {G}.

Flying

{U}, Sacrifice Glen Elendra Archmage: Counter target noncreature spell.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Draw a card. You may put a land card from your hand onto the battlefield.

Evolve (Whenever a creature enters the battlefield under your control, 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.

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control. Then if that creature has three or more +1/+1 counters on it, transform Hadana's Climb.

(Transforms from Hadana's Climb.)

{T}: Add one mana of any color.

{1}{G}{U}, {T}: Target creature you control gains flying and gets +X/+X until end of turn, where X is its power.

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 it instead.

Creatures you control with +1/+1 counters on them can't be blocked.

Permanents you control gain hexproof and indestructible until end of turn.

When you cast this spell, you gain half X life and draw half X cards. Round down each time.

Flying, trample

Hydroid Krasis enters the battlefield with X +1/+1 counters on it.

Put five +1/+1 counters on target creature. If this spell was cast from a graveyard, put ten +1/+1 counters on that creature instead.

Flashback {5}{G}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

{T}: Add one mana of any type that a land you control could produce. If Incubation Druid has a +1/+1 counter on it, add three mana of that type instead.

{3}{G}{G}: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)

{T}: Add {G}.

Llanowar Reborn enters the battlefield tapped.

{T}: Add {G}.

Graft 1 (This land enters the battlefield with a +1/+1 counter on it. Whenever a creature enters the battlefield, you may move a +1/+1 counter from this land onto it.)

Trample

Whenever a player casts a spell, put a +1/+1 counter on Managorger Hydra.

Each other creature you control enters the battlefield with a number of additional +1/+1 counters on it equal to Master Biomancer's power and as a Mutant in addition to its other types.

Other green creatures you control get +1/+1.

Other blue creatures you control get +1/+1.

Untap all green and/or blue creatures you control during each other player's untap step.

Devour 2 (As this enters the battlefield, you may sacrifice any number of creatures. This creature enters the battlefield with twice that many +1/+1 counters on it.)

At the beginning of your upkeep, create a 1/1 green Saproling creature token for each +1/+1 counter on Mycoloth.

Whenever a creature enters the battlefield under your control, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on the creature, then put the card back or put it into your graveyard.)

For each player, choose friend or foe. Each friend searches their library for a land card, puts it onto the battlefield tapped, then shuffles. Each foe sacrifices an artifact or enchantment they control.

Partner with Toothy, Imaginary Friend (When this creature enters the battlefield, target player may put Toothy into their hand from their library, then shuffle.)

If one or more counters would be put on a permanent your team controls, that many plus one of each of those kinds of counters are put on that permanent instead.

Graft 3 (This creature enters the battlefield with three +1/+1 counters on it. Whenever another creature enters the battlefield, you may move a +1/+1 counter from this creature onto it.)

{2}: Target creature with a +1/+1 counter on it gains shroud until end of turn. (It can't be the target of spells or abilities.)

Prime Speaker Zegana enters the battlefield with X +1/+1 counters on it, where X is the greatest power among other creatures you control.

When Prime Speaker Zegana enters the battlefield, draw cards equal to its power.

Primordial Hydra enters the battlefield with X +1/+1 counters on it.

At the beginning of your upkeep, double the number of +1/+1 counters on Primordial Hydra.

Primordial Hydra has trample as long as it has ten or more +1/+1 counters on it.

{G}: Exile target card from a graveyard. If it was a creature card, put a +1/+1 counter on Scavenging Ooze and you gain 1 life.

At the beginning of your upkeep, if you control five or more lands, put four +1/+1 counters on Scute Mob.

{1}{G}{U}: Put a +1/+1 counter on target creature you control.

Whenever one or more +1/+1 counters are put on a creature you control, put that many growth counters on Simic Ascendancy.

At the beginning of your upkeep, if Simic Ascendancy has twenty or more growth counters on it, you win the game.

Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

{T}, Remove one or more +1/+1 counters from Simic Manipulator: Gain control of target creature with power less than or equal to the number of +1/+1 counters removed this way.

Spike Weaver enters the battlefield with three +1/+1 counters on it.

{2}, Remove a +1/+1 counter from Spike Weaver: Put a +1/+1 counter on target creature.

{1}, Remove a +1/+1 counter from Spike Weaver: Prevent all combat damage that would be dealt this turn.

({U/P} can be paid with either {U} or 2 life.)

Draw two cards, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Partner with Pir, Imaginative Rascal (When this creature enters the battlefield, target player may put Pir into their hand from their library, then shuffle.)

Whenever you draw a card, put a +1/+1 counter on Toothy, Imaginary Friend.

When Toothy leaves the battlefield, draw a card for each +1/+1 counter on it.

Vivid Creek enters the battlefield tapped with two charge counters on it.

{T}: Add {U}.

{T}, Remove a charge counter from Vivid Creek: Add one mana of any color.

Vivid Grove enters the battlefield tapped with two charge counters on it.

{T}: Add {G}.

{T}, Remove a charge counter from Vivid Grove: Add one mana of any color.

{G}{U}, {T}: Double the number of each kind of counter on target artifact, creature, or land.

When Zegana, Utopian Speaker enters the battlefield, if you control another creature with a +1/+1 counter on it, draw a card.

{4}{G}{U}: Adapt 4. (If this creature has no +1/+1 counters on it, put four +1/+1 counters on it.)

Each creature you control with a +1/+1 counter on it has trample.