Chromatog
Creature - Atog
Sacrifice another permanent: ~ gets +1/+1 until end of turn for each of that permanent's colors.
2/2
raphy

Unstoppable Might
Instant
Target creature gets +0/+4 and gains double strike until end of turn.

Dromaka's Command
Instant
Choose two:
-Destroy all artifacts
-Destroy all enchantments
-Put a 5/5 green beast creature token onto the battlefield
-Target creature gets +5/+5 and gains trample until end of turn

Uninformed Decision
Sorcery
Look at the top 3 cards of your library, then separate them into a face up pile and a face down pile. An opponent chooses one of them. Put that pile into your hand and the other pile into your graveyard.
"Humans fear many things; demons, dragons, titans, and most of all, the unknown."
-Alys, Sphinx of Jwar Isle

Oblivion Elemental
Creature - Elemental
Morph: Discard your hand.
4/4

Aether Edict
Instant
Target player puts a creature they control on top of its owner's library.

Reality Rift
Instant
Exile target creature, then return it to the battlefield under its owner's control at the beginning of the next end step.
Draw a card.

Deny
Instant
Deny costs less to cast for each spell an opponent has cast this turn.
Counter target spell.

Wade Into Battle
Instant
~ deals 3 damage to target creature or player. If a creature is dealt damage this way, it deals damage equal to its power to you.

Boros Battlemaster
Creature - Human Soldier
, : Target creature can't attack this turn.
, : Target creature can't block this turn.
1/1

Frostbite
Instant
~ deals 2 damage divided as you choose between one or two target creatures and/or players. Tap each creature dealt damage this way. It doesn't untap during its controller's next untap step.

Ferocious Boar
Creature - Boar
~ enters the battlefield with 2 +1/+1 counters on it.
Remove a +1/+1 counter from ~: ~ gets +2/+2 until end of turn.
0/0

Yeah, I know, Sawtooth Thresher already did this, but that card sucked.

Unstoppable Charge
Instant
Target creature gets +2/+2 and gains trample until end of turn. Return any number of target creatures blocking or blocked by it to their owners' hands.
The lucky soldiers were cast aside by the force of the charge.

Shadow Razes
Instant
Choose one, two or three:
-Destroy target attacking or blocking creature.
-Destroy target tapped, non-attacking, non-blocking creature.
-Destroy target untapped, non-attacking, non-blocking creature.

Necromastery
Enchantment
Whenever a creature dealt damage by a source you control this turn dies, put a soul counter on ~.
Creatures you control get +1/+0 for each soul counter on ~.
Sacrifice ~: ~ deals damage equal to the number of soul counters on it to each opponent and each creature your opponents control.

Presence of the Dark Lord
Enchantment
If a source you control would deal damage, it deals that much damage plus 1 instead.

Duel
Instant
Target creature you control fights target creature. When either of those creatures dies this turn, put 3 +1/+1 counters on the other.

Battle Trance
Instant
Creatures you control gain double strike until end of turn.

Boros Striker
Creature - Human Soldier
~ enters the battlefield with 2 +1/+1 counters on it.
Remove +1/+1 counter from ~: ~ gains double strike until end of turn.
0/0

Master of Toxins
Creature - Human Assassin
~ enters the battlefield with 2 +1/+1 counters on it.
Remove a +1/+1 counter from ~: ~ gains deathtouch until end of turn.
0/1

Meltdown Elemental
Creature - Elemental
~ enters the battlefield with 2 +1/+1 counters on it.
Remove a +1/+1 counter from ~: when ~ dies this turn, it deals damage equal to its power to target creature or player.
1/0

Flock of Phantasms
Creature - Illusion
Flying
~ enters the battlefield with 2 +1/+1 counters on it.
Remove a +1/+1 counter from ~: Until end of turn, ~ becomes a 3/3 Illusion with "whenever this creature becomes the target of a spell or ability, sacrifice it."
0/0

Ravenous Hunger
Enchantment - Aura
Enchant Creature
At the beginning of enchanted creature's controller's upkeep, that player sacrifices a creature.

Fleeting Inspiration
Instant
Exile the top card of your library. You may play that card this turn.
Rebound

See the World
Sorcery
Search your library for a basic land card and put it onto the battlefield tapped, then shuffle your libary.
Rebound

Phase Shift
Instant
Exile target creature. Return it to the battlefield under its owner's control at the beginning of the next end step.
Rebound

Recurrence
Instant
Target instant or sorcery card in your graveyard gains flashback until end of turn. Its flashback cost is equal to its mana cost.
Rebound

Faltering Sanity
Sorcery
Name a card, then target player reveals their hand. That player discards all cards with that name.
Rebound

Valiant Effort
Instant
Bolster 1
Draw a card.

Duplicate
Instant
Target spell gains rebound.
Draw a card.

Surprise Assault
Sorcery
Creature cards in your hand gain dash until end of turn. Their dash cost is equal to their mana cost.
Draw a card.

Daghatar, the Enduring
Legendary Creature - Human Warrior
Creatures you control have outlast
2/3

Echo
Legendary Creature - Nymph
Whenever you cast an instant or sorcery spell targeting ~, it gains rebound.
2/2

Narcissus
Legendary Creature - Human Advisor
Whenever a creature blocks or becomes blocked by ~, that creature becomes a copy of ~.
1/1

Waning Rift
Instant
~ deals 3 damage to target creature or player. Creatures dealt damage this way lose all abilities until end of turn. Players dealt damage this way can't cast noncreature spells until end of turn..

copying legendary creatures isn't cute

I'm considering nominating these cards for CotW, not sure which ones though. They are all mechanically interesting in their own way.

All of them. All the other ones too. Hell, copypaste this whole thread into CotW.

Boros War Machine
Artifact Creature - Juggernaut
~ can't attack unless you control a mountain.
~ can't block unless you control a plains.
4/4

Aethermancer
Creature - Human Wizard
When ~ dies, you may put target creature on top of its owner's library.
2/2

Empower
Instant
Bolster 1. Target creature gets +1/+1 until end of turn.

Empower would be so much cooler reversed.

There's an argument for both sides, but I agree with you.

I like it as is, because it makes it easier to +2/+2 a guy if you want to.

Fiery Soul
Creature - Elemental
Whenever you cast an instant or sorcery spell, ~ gains first strike until end of turn. If it already had first strike, it gains double strike instead.
2/1

I would change the wording here. I understand the "reading experience" (that is, the first contact with the card) is much more awesome if you are first presented the first strike, and then the double strike, but I'm hesitant to use "already" in a card.

Actually, I just checked and there are cards that use "already" as non-reminder text (most notably Final Punishment and Whipkeeper). So screw it, and keep the awesome wording experience. Just remember to add the "until end of turn" on the double strike instead-clause too. Or, in case, it was meant to be permanent, I'd suggest something to alleviate memory issues.

That aside, the card is pretty awesome. I like it a lot.

Edict of Eradiction
Instant
Target opponent chooses a creature they control. You may destroy that creature. If you don't, destroy all other creatures.

Rupture
Enchantment - Aura
Enchant creature
Whenever enchanted creature attacks or blocks, ~ deals 5 damage to it.

Styrgwyr, Blood Seeker
Legendary Creature - Human Warrior
~ gets +1/+1 for each opponent that was dealt damage this turn and each creature you don't control that was dealt damage this turn.
: ~ fights target creature that was dealt damage this turn.
2/2

DotA 2

Faceless Void
Legendary Creature - Whatever
(Faceless Void is [insert colors])
Morph X (Text)
Power/Toughness

Strong Weakness // Weak Strength //
Instant
Target creature gets -3/-3 until end of turn.
//
Destroy target creature with toughness 4 or greater.
Fuse

Castle // Siege //
Instant
Until end of turn, target creature loses all abilities and becomes an 0/4 wall with defender.
//
Destroy target creature if it has toughness 4 or greater.
Fuse

Frenetic Spellcraft
Instant
Counter target spell. Draw X cards, then discard X cards.

Overthink
Instant
Counter target spell, then draw a card unless that spell's controller pays .

Restrict
Instant
Counter target spell unless its controller puts x cards from their hand on top on their library.

Deny
Instant
Counter target spell unless its controller pays
Flashback

Mindwipe
Instant
Return target spell to its owner's hand, then look at that player's hand. You may choose a nonland card from it. If you do, that player discards that card.

Mindwipe is reaaally nice.

For that awkward of a mana cost, it had damn well better be.