As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

This spell costs less to cast, where X is the greatest number of artifacts an opponent controls.
Flying, trample, haste
Whenever this creature deals combat damage to a player, you create a Treasure token for each artifact that player controls.

(: Add .)

Prevent all damage that would be dealt to Cho-Manno.

When Mjölnir enters, it deals 4 damage to up to one target creature.
Double all damage equipped creature would deal.
Equip worthy (A creature is worthy if it's a legendary non-Villain that's red and/or white.)
, Discard this card: It deals 2 damage to each creature.

Enchant creature
: Tap enchanted creature.
: Untap enchanted creature.

At the beginning of each player's upkeep, that player chooses target player who controls more creatures than they do and is their opponent. The first player may reveal cards from the top of their library until they reveal a creature card. If the first player does, that player puts that card onto the battlefield and all other cards revealed this way into their graveyard.

: Add .
: Add . Spend this mana only to cast colorless Eldrazi spells or activate abilities of colorless Eldrazi.

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a Human deals damage to you, destroy it.
Other non-Human creatures you control get +1/+1 and have undying. (When a creature with undying 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.)

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Zack Fair enters with a +1/+1 counter on it.
, Sacrifice Zack Fair: Target creature you control gains indestructible until end of turn. Put Zack Fair's counters on that creature and attach an Equipment that was attached to Zack Fair to that creature.

Vigilance
Whenever a source an opponent controls deals damage to you or a permanent you control, that source's controller loses 2 life unless they pay .
, Sacrifice three other creatures: Exile Elesh Norn, then return it to the battlefield transformed under its owner's control. Activate only as a sorcery.

Throw ... — , Unattach an Equipment from Captain America: He deals damage equal to that Equipment's mana value divided as you choose among one, two, or three targets.
... Catch — At the beginning of combat on your turn, attach up to one target Equipment you control to Captain America.

As an additional cost to cast this spell, sacrifice a green creature.
Search your library for a green creature card, put it onto the battlefield, then shuffle.

You may play lands from your graveyard.

, Pay 1 life, Sacrifice this land: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

: Add .
Ferocious — : Add . Activate only if you control a creature with power 4 or greater.
Eternalize (, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Snake Druid with no mana cost. Eternalize only as a sorcery.)

Flying
Spells your opponents cast that target this creature cost an additional 3 life to cast.
Whenever another creature you control enters, this creature deals damage equal to that creature's power to any target.

When Omnath enters, draw a card.
Landfall — Whenever a land you control enters, you gain 4 life if this is the first time this ability has resolved this turn. If it's the second time, add . If it's the third time, Omnath deals 4 damage to each opponent and each planeswalker you don't control.

Whenever you cast a green spell and whenever a Forest you control enters, put a +1/+1 counter on target creature you control.
: Add .