Your opponents can't cast spells with even mana values. (Zero is even.)
Your opponents can't block with creatures with even mana values.

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays , where X is this creature's power.

You may have this artifact enter as a copy of any artifact on the battlefield.

Whenever a land is put into a graveyard from the battlefield, this artifact deals 2 damage to that land's controller.

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to that card's mana value.

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.

Search your library for a card, put that card into your hand, discard a card at random, then shuffle.

Tap an untapped Druid you control: Add .

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

+1: Reveal the top five cards of your library. Put all creature cards revealed this way into your hand and the rest on the bottom of your library in any order.
−3: You may put a green creature card from your hand onto the battlefield.
−7: You get an emblem with "Whenever you cast a creature spell, you may search your library for a creature card, put it onto the battlefield, then shuffle."

Tetsuo Umezawa can't be the target of Aura spells.
, : Destroy target tapped or blocking creature.

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
: Add , , or .

: Add .
, Sacrifice this land: Destroy target land.

Flying
When Smaug enters, create X tapped Treasure tokens, where X is the number of artifacts your opponents control.
Whenever you cast a spell, if mana from a Treasure was spent to cast it, you draw a card and lose 1 life.

Sacrifice an artifact: Put a +1/+1 counter on this creature.
Modular 1 (This creature enters with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Target creature gets +3/+3 until end of turn.

If it's not your turn, you may exile a green card from your hand rather than pay this spell's mana cost.
Destroy up to two target artifacts and/or enchantments.

Whenever you cast a red spell, untap Chandra.
: Chandra deals 1 damage to target player or planeswalker. If Chandra has dealt 3 or more damage this turn, exile her, then return her to the battlefield transformed under her owner's control.

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
You can't lose the game this turn and your opponents can't win the game this turn. Until end of turn, damage that would reduce your life total to less than 1 reduces it to 1 instead.

Each player's life total becomes the number of creatures they control.