If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Ward—Sacrifice a legendary artifact or legendary creature.
Whenever an opponent casts a spell, amass Orcs 1.
Whenever an Army you control deals combat damage to a player, the Ring tempts you.
Whenever the Ring tempts you, you may discard your hand. If you do, draw four cards.

Flash
Vigilance
Aegis of the Emperor — Commanders you control have protection from everything.

: Target creature you control gains protection from the color of your choice until end of turn.

This creature gets +1/+1 for each other creature on the battlefield named Relentless Rats.
A deck can have any number of cards named Relentless Rats.

Vigilance
When this creature enters, each player chooses an artifact, a creature, an enchantment, and a planeswalker from among the nonland permanents they control, then sacrifices the rest.

Whenever an opponent loses life, you gain that much life.

Umbris gets +1/+1 for each card your opponents own in exile.
Whenever Umbris or another Nightmare or Horror you control enters, target opponent exiles cards from the top of their library until they exile a land card.

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip

Trample
You may cast creature cards from your hand as though they were the card Colossal Dreadmaw. (They become Colossal Dreadmaws.)

+2: Create a 1/1 green Elf Druid creature token with ": Add ."
−2: Destroy target artifact or enchantment.
−6: Draw a card for each green creature you control.
Freyalise, Llanowar's Fury can be your commander.

Defender (This creature can't attack.)
: Regenerate this creature.

Dragon spells you cast cost less to cast.
Whenever a Dragon you control enters, you may have Sarkhan become a copy of it until end of turn, except its name is Sarkhan, Soul Aflame and it's legendary in addition to its other types.

Horsemanship (This creature can't be blocked except by creatures with horsemanship.)
This creature can't block.

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Add for each card in target opponent's hand.
• Exile the top three cards of your library. You may play them this turn.

When this creature enters, you may search your library for an artifact card with mana value 1 or less, reveal that card, put it into your hand, then shuffle.

+2: Ugin deals 3 damage to any target.
−X: Exile each permanent with mana value X or less that's one or more colors.
−10: You gain 7 life, draw seven cards, then put up to seven permanent cards from your hand onto the battlefield.

Haste (This creature can attack and as soon as it comes under your control.)
: Kamahl deals 3 damage to any target.

Flying, vigilance, indestructible
Other permanents you control have indestructible.

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Whenever one or more creatures you control with power 7 or greater deal combat damage to a player, untap all creatures you control. If it's the first combat phase of your turn, there is an additional combat phase after this phase.