msem-instigator

Whenever a land you control enters, add one mana of any color.
Whenever Enraged Fangwurm attacks, you may sacrifice a land. If you do, Enraged Fangwurm deals 2 damage to target player or planeswalker.

Trample
Whenever a creature you control with trample is dealt damage, put a +1/+1 counter on it. (It must survive the damage to get the counter.)

Prowess

Enchant opponent
At the beginning of enchanted player's upkeep, they choose one that hasn't been chosen yet —
• They discard three cards.
• They sacrifice three nonland permanents.
• You transform Enrapturing Grudge.
If Enrapturing Grudge would be put into a graveyard from anywhere, exile it instead.

Enchant creature
Enchanted creature loses all abilities and is a blue Wizard creature with base power and toughness 1/1.

Enshrouded Village enters tapped.
{T}: Add {G}.
{1}{G}{G}: Until end of turn, Enshrouded Village becomes a 4/4 Human creature with trample. Activate only if you're horrific.

Whenever Ensnaring Possessor attacks, you may tap or untap target permanent.
{1}{U}, {T}: Until end of turn, target creature gets +1/+1 and gains “Whenever this creature attacks, you may tap or untap target permanent.” Activate only as a sorcery.

Enchant creature
Enchanted creature has reach. (It can block creatures with flying)
{G}, Sacrifice Ensnaring Vines: Tap target creature with flying.

Ward—Pay 5 life.
Whenever Ensouled Savior deals combat damage while attacking, you get five glory counters. (You lose glory counters before life. A player with ten or more glory counters wins the game.)

Whenever Ensouled Thief attacks, upgrade it. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Prowess

{1}: Target Equipment becomes a colorless 3/3 Construct artifact creature until end of turn. (Equipment that's a creature can't equip a creature.)
{2}{U}{U}, {T}: Return target artifact card from your graveyard to your hand.

Flying
Whenever Entali Aeromancer attacks, Elementals you control gain flying until end of turn.

Landfall — Whenever a land you control enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Whenever you make first contact, exile the top card of your library. You gain life equal to its mana value. You may play that card until the end of your next turn. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

Hexproof
At the beginning of your upkeep, target instant or sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost.

Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on Entelan Duelist.
{2}{U}{R}, Remove two +1/+1 counters from Entelan Duelist: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Whenever you make first contact, Entelan Idealist gets +2/+2 until end of turn. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

When Entelan Savant enters, scry 2.

Once each turn, when you cast a spell, you may note one of its card types that hasn't been noted for Enter Captain Minnow. If you do, create a number of tapped Treasure tokens equal to the number of types noted for Enter Captain Minnow.

As long as it's your turn, planeswalkers you control are X/X creatures with indestructible that are still planeswalkers, where X is the number of loyalty counters on them.
Prevent all damage that would be dealt to planeswalkers you control during your turn.

When Enter the Wormhole enters or leaves the battlefield, draw a card.
Whenever you cast a noncreature spell, target player mills a card.

Improve {1} ({1}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
{T}: Add one mana of any color.
{T}: Add X mana of any one color, where X is the greatest number of counters among creatures you control.

Harmony — Draw a card.
When Enthralling Actor enters, harmonize. (Trigger up to one harmony of one permanent you control.)

Whenever a Role is attached to a creature you control or you cast a spell that targets a creature you control, put a +1/+1 counter on Enthusiastic Admirer.

You may have Enthusiastic Double enter as a copy of any permanent on the battlefield, except it's 4/4, it's a creature in addition to its other types, and it has haste.