msem-instigator

Trample
When Arborback Stomper enters, you gain 5 life.

As long as Arboreal Runes is on the battlefield or in your graveyard, it's a Forest land in addition to its other types.
{T}: Add one mana of any color.

Flash
Enchant creature
When Arcane Anesthesia enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Counter target spell. If a permanent spell is countered this way, create a Gold token. (It's an artifact with “Sacrifice this artifact: Add one mana of any color.”)

Enchant creature
Enchanted creature gets +1/+1 and has flying and prowess.

Prowess
When Arcane Dredger enters, return target instant or sorcery card from your graveyard to your hand.

Whenever Arcane Duelist becomes tapped, target instant or sorcery card with mana value 1 in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost. (You may cast that card from your graveyard for its flashback cost. Then exile it.)

{U}, Exile an instant or sorcery card from your graveyard: Draw a card, then discard a card.
{R}, Exile an instant or sorcery card from your graveyard: Arcane Harvesters deals 1 damage to any target.

Search your library for an instant or sorcery card, reveal it, put it into your hand, then shuffle.

Arcane Oasis enters tapped unless you control another Desert.
{T}: Add {U} or {R}.

Counter target spell.
Look at the top three cards of your library. Put one on top and the rest on the bottom in any order.

Arcane Sanctum enters tapped.
{T}: Add {W}, {U}, or {B}.

Harmony — Attach Arcane Saxophone to target creature.
When Arcane Saxophone enters, harmonize. (Trigger up to one harmony of one permanent you control.)
Equipped creature gets +2/+2.
Equip {4}

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

Whenever you cast a spell, draw a card if that spell has the same name as a card in your graveyard.

Counter target spell unless its controller pays {2}.
Reprise {3}{U} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Until end of turn, creatures you control get +1/+1 and gain prowess. If there are two or more instant and/or sorcery cards in your graveyard, draw a card.

Equipped creature gets +1/+0.
Whenever equipped creature attacks, you may draw a card then discard a card.
Equip {2}

When Arcanomancer enters, return up to one target instant card and up to one target sorcery card from your graveyard to your hand.

Counter target instant or sorcery spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Flying
When Arcanum Owl enters, you may return target instant or sorcery card from your graveyard to your hand.

Lifelink
Arcblade Enforcers gets +1/+1 as long as you control an enchantment.

Wanderlust — When you cast this spell, you may copy it if you control four or more differently named lands.
Exile the top card of your library. Until the end of your next turn, you may play that card. Create a 1/1 Scout creature token that's all colors.

Gain control of target artifact or creature until end of turn. Untap it. It gains haste until end of turn.