Timberland Guide

When Timberland Guide enters, put a +1/+1 counter on target creature.

Essence Scatter

Runes of the Deus

Enchant creature
As long as enchanted creature is red, it gets +1/+1 and has double strike. (It deals both first-strike and regular combat damage.)
As long as enchanted creature is green, it gets +1/+1 and has trample.

Floodchaser

Floodchaser enters with six +1/+1 counters on it.
Floodchaser can't attack unless defending player controls an Island.
{U}, Remove a +1/+1 counter from Floodchaser: Target land becomes an Island until end of turn.

Ascendant Packleader

Ascendant Packleader enters with a +1/+1 counter on it if you control a permanent with mana value 4 or greater.
Whenever you cast a spell with mana value 4 or greater, put a +1/+1 counter on Ascendant Packleader.

Briar Hydra

Trample
Domain — Whenever Briar Hydra deals combat damage to a player, put X +1/+1 counters on target creature you control, where X is the number of basic land types among lands you control.

Seshiro's Living Legacy

Tales of Master Seshiro

(As this Saga enters and after your draw step, add a lore counter.)
I, II — Put a +1/+1 counter on target creature or Vehicle you control. It gains vigilance until end of turn.
III — Exile this Saga, then return it to the battlefield transformed under your control.

Tales of Master Seshiro // Seshiro's Living Legacy

Backup Agent

When Backup Agent enters, put a +1/+1 counter on target creature.

Deathbloom Gardener

Deathtouch
{T}: Add one mana of any color.

Trapjaw Kelpie

Flash
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.)

Negate

Travel Preparations

Put a +1/+1 counter on each of up to two target creatures.
Flashback {1}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Seer's Lantern

{T}: Add {C}.
{2}, {T}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Zar Ojanen, Scion of Efrava

Domain — Whenever Zar Ojanen, Scion of Efrava becomes tapped, put a +1/+1 counter on each creature you control with toughness less than the number of basic land types among lands you control.

Pixie Illusionist

Kicker {3}{G} (You may pay an additional {3}{G} as you cast this spell.)
Flying
If Pixie Illusionist was kicked, it enters with two +1/+1 counters on it.
{T}: Target land you control becomes the basic land type of your choice until end of turn.

Seven-Tail Mentor

When Seven-Tail Mentor enters or dies, put a +1/+1 counter on target creature or Vehicle you control.

Scourge of the Nobilis

Enchant creature
As long as enchanted creature is red, it gets +1/+1 and has "{R/W}: This creature gets +1/+0 until end of turn."
As long as enchanted creature is white, it gets +1/+1 and has lifelink. (Damage dealt by the creature also causes its controller to gain that much life.)

Sinking Feeling

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.
Enchanted creature has "{1}, Put a -1/-1 counter on this creature: Untap this creature."

Divination

Simic Ascendancy

{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.

Incremental Growth

Put a +1/+1 counter on target creature, two +1/+1 counters on another target creature, and three +1/+1 counters on a third target creature.

Tatyova, Steward of Tides

Land creatures you control have flying.
Whenever a land you control enters, if you control seven or more lands, up to one target land you control becomes a 3/3 Elemental creature with haste. It's still a land.

Rendclaw Trow

Wither (This deals damage to creatures in the form of -1/-1 counters.)
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.)