Ivy, Gleeful Spellthief

Flying
Whenever a player casts a spell that targets only a single creature other than Ivy, Gleeful Spellthief, you may copy that spell. The copy targets Ivy. (A copy of an Aura spell becomes a token.)

Gaea's Gift

Put a +1/+1 counter on target creature you control. It gains reach, trample, hexproof, and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Vesuvan Duplimancy

Whenever you cast a spell that targets only a single artifact or creature you control, create a token that's a copy of that artifact or creature, except it's not legendary.

Fyndhorn Elves

One with Nature

Enchant creature
Whenever enchanted creature deals combat damage to a player, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Forest

Birds of Paradise

Tamiyo's Safekeeping

Target permanent you control gains hexproof and indestructible until end of turn. You gain 2 life. (A permanent with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Royal Treatment

Target creature you control gains hexproof until end of turn. Create a Royal Role token attached to that creature. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has ward {1}.)

Charge Through

Target creature gains trample until end of turn.
Draw a card.

Well Rested

Enchant creature
Enchanted creature has "Whenever this creature becomes untapped, put two +1/+1 counters on it, then you gain 2 life and draw a card. This ability triggers only once each turn."

Cerulean Wisps

Target creature becomes blue until end of turn. Untap that creature.
Draw a card.

Hunter's Insight

Choose target creature you control. Whenever that creature deals combat damage to a player or planeswalker this turn, draw that many cards.

Artisan of Forms

Heroic — Whenever you cast a spell that targets Artisan of Forms, you may have Artisan of Forms become a copy of target creature, except it has this ability.

Triton Fortune Hunter

Heroic — Whenever you cast a spell that targets Triton Fortune Hunter, draw a card.

Adrix and Nev, Twincasters

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
If one or more tokens would be created under your control, twice that many of those tokens are created instead.

Llanowar Elves

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Corrupted Conscience

Enchant creature
You control enchanted creature.
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Arcane Signet

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

Quantum Misalignment

Create a token that's a copy of target creature you control, except it isn't legendary.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Elvish Mystic

Stormchaser Drake

Flying
Whenever Stormchaser Drake becomes the target of a spell you control, draw a card.

Timber Paladin

As long as Timber Paladin is enchanted by exactly one Aura, it has base power and toughness 3/3.
As long as Timber Paladin is enchanted by exactly two Auras, it has base power and toughness 5/5 and vigilance.
As long as Timber Paladin is enchanted by three or more Auras, it has base power and toughness 10/10, vigilance, and trample.

Spellwild Ouphe

Spells that target Spellwild Ouphe cost {2} less to cast.

Orvar, the All-Form

Changeling
Whenever you cast an instant or sorcery spell, if it targets one or more other permanents you control, create a token that's a copy of one of those permanents.
When a spell or ability an opponent controls causes you to discard this card, create a token that's a copy of target permanent.

Season of Growth

Whenever a creature you control enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Whenever you cast a spell that targets a creature you control, draw a card.

Twinning Staff

If you would copy a spell one or more times, instead copy it that many times plus an additional time. You may choose new targets for the additional copy.
{7}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Double Major

Copy target creature spell you control, except it isn't legendary if the spell is legendary. (A copy of a creature spell becomes a token.)

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Scale the Heights

Put a +1/+1 counter on up to one target creature. You gain 2 life. You may play an additional land this turn.
Draw a card.

Errant, Street Artist

Flash
Defender, haste
{1}{U}, {T}: Copy target spell you control that wasn't cast. You may choose new targets for the copy.

Ancestral Mask

Enchant creature
Enchanted creature gets +2/+2 for each other enchantment on the battlefield.

Shadow Rift

Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)
Draw a card.

Island

Sage of Hours

Heroic — Whenever you cast a spell that targets Sage of Hours, put a +1/+1 counter on it.
Remove all +1/+1 counters from Sage of Hours: For each five counters removed this way, take an extra turn after this one.

Gnarlback Rhino

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever you cast a spell that targets Gnarlback Rhino, draw a card.

Hunter's Prowess

Until end of turn, target creature gets +3/+3 and gains trample and "Whenever this creature deals combat damage to a player, draw that many cards."

Command Tower

Eel Umbra

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
Enchanted creature gets +1/+1.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Rune of Might

Enchant permanent
When Rune of Might enters, draw a card.
As long as enchanted permanent is a creature, it gets +1/+1 and has trample.
As long as enchanted permanent is an Equipment, it has "Equipped creature gets +1/+1 and has trample."