Make your own Magic card!

The only issue I can see is that it would require the players to keep track of which Eldrazi caused the sacrifice/exiled of what, which would become even hairier if you were using It That Betrays.

Suppose it were something like, "Whenever the ability of an Eldrazi an opponent controls would cause you to exile a card, exile it attached to Indigestion," with a fairly expensive ability that lets you sacrifice it to do the "tap and doesn't untap during next untap step" thing to a target Eldrazi and borf out the cards attached to it?

At any rate, would it make sense to give the spell Devoid?

edited 18th Aug '15 8:51:53 PM by Durazno

Purity of Purpose (WW)
Enchantment
Players can't use colored mana to cast spells not of that color.

edited 18th Aug '15 9:08:05 PM by IrishZombie

Delving beyond Delving - UUBBBG
Enchantment
Exile a card from your graveyard: add {1} to your mana pool.
{3}: Put target face-up exiled card you own into your graveyard.
It doesn't matter how deep you have to delve as long as you win.

Skyball Paint (1BR)
Legendary Creature - Horse
2/2
Whenever ~ becomes paired with a creature, that creature gets +2/+0 and gains haste and flying until end of turn. Sacrifice it at the beginning of the next end step.
Good men have tried this horse to ride, but most of 'em are dead.

edited 18th Aug '15 11:15:12 PM by CountDorku

Discontent - 1R
Sorcery
Target creature you don't control fights a random creature controlled by the same player.

edited 19th Aug '15 12:56:31 PM by Noaqiyeum

@Irish Zombie: That is an absolutely brutal multicolor hoser in the early game. I like it.

Seek the Distant Shore - 2G
Sorcery
When you cast ~ search your library for a basic Land card.

Put a Land card from your hand onto the battlefield tapped.

It costs more than Rampant Growth, but can put a non-basic land you have in your hand on to the battlefield and can only be partially countered.

edited 19th Aug '15 12:59:41 PM by BigMadDraco

I'd put "when you cast" instant/sorceries in red, personally, while green should get it on creatures - same distribution as "can't be countered".

Stormspark (1RR)
Sorcery
When you cast ~, choose a creature or enchantment you control. That permanent deals 1 damage to target creature.
~ deals 2 damage to target creature or player.

(This is worded slightly strangely because I'm not sure if you're allowed to deal damage directly from effects that haven't resolved yet.)

Grove Artisan (3G)
Creature - Elf Druid
1/1
When you cast ~, search your library for a basic land card, reveal it, and put it into your hand. Shuffle your library afterwards.
When ~ enters the battlefield, you may put a land card from your hand onto the battlefield.

A thought occurred to me: What if the key to getting 4-colored commanders isn't to try to figure out how to make 4-colored creatures, but instead to try to focus on using color identity to make them work instead, in the style of the Fate Reforged legendary Kahns?

For example:

Maiden of War 2WW
Legendary Creature - Angel Warrior
Flying
UU: Scry 1.
1R: Until end of turn, target creature gains "R: This creature gains +1/+0 until end of turn".
2G: Target creature you control fights target creature you don't control.
2/5

Scorn, Draconic Overlord 3RR
Legendary Creature - Dragon Shaman
Flying
When a dragon creature you control deals damage to a creature you don't control, if that creature dies this turn, you may pay 2GG. If you do, search your library for a land card, reveal it, then put it into your hand.
1B: Target Dragon creature you control gains Deathtouch until end of turn.
2U: Draw a card, then discard a card.
5/5

Jargis, Guardian Sphinx 4U
Legendary Creature - Sphinx Wizard
Flying
1R: Target creature gains Prowess until end of turn.
2W: Target creature gains First Strike until end of turn.
B: Exile X cards from your graveyard. Add X to your mana pool.
4/4

And keep in mind I'm not thinking about balance with these, just the concept behind 4-color commanders that aren't 4-color creatures.\\

That would make them a lot easier to manage, though I wonder how you'd balance the colors of their deck. I like the way you did it here; I've always thought that creatures with varied activated abilities felt more like commanders.

Another way to handle the thematic issue would be to make the four-color creature cards represent inseparable duos, like Anax and Cymede.

Or even do both.

Picking a random duo:

Fireman and Iceman (2UBRG)
Legendary Artifact Creature - Elemental
5/5
Whenever ~ attacks, you may pay either 3WU or 3RG. If you paid 3WU, tap up to two target creatures the defending player controls. They don't untap during their controller's next untap step. If you paid 3RG, ~ deals damage equal to its power to target creature defending player controls.

One for the Money - WU
Enchantment
Whenever you a permanent you control becomes untapped, except during your untap step, you gain 1 life.

Two for the Show - 1WWU
Enchantment
Whenever a spell you control counters a spell or ability, put two 0/1 blue and white bird creature tokens with flying onto the battlefield.

Three to Get Ready - 3WWUU
Enchantment
At the beginning of your end step, draw three cards.

Go Cat, Go! - WU
Legendary Creature - Cat
{1}: If you control enchantments named One for the Money, Two for the Show, and Three to Get Ready, put a legendary blue Equipment artifact token named Blue Suede Shoes onto the battlefield. It has indestructible, "Equipped creature gets +4/+4 and has indestructible, vigilance, and flying," and Equip {0}.
1/1

edited 24th Aug '15 8:53:10 PM by kagescorpionakki

Missing P/T.

Card tax:

Thimphu, Stronghold of the Jeskai

Legendary Land

T: Add R, W, or U to your mana pool.

RWU, T: Deal damage to target creature or player equal to half the number of instants or sorceries in your graveyard, rounded up.

Not quite sure how to word the last bit.

edited 27th Aug '15 9:44:21 AM by Tojin

Thanks.

Also, "~ deals damage to target creature or player equal to half the number of instant and sorcery cards in your graveyard, rounded down/up."

Thanks.

Re: Citadel of the Jeskai,

Aren't citadels Abzan's thing?

Edit: Or "weren't", more accurately.

edited 27th Aug '15 2:04:20 AM by ImperialSunlight

Probably, but I can't think of a more suitable name for it.

Use "Stronghold" for the Jeskai. Most of the named locations in their territories are called that.

Thanks much. Editing right now.

Double or Nothing - UR
Enchantment
When a player casts an instant or sorcery spell, that player may flip a coin. If he or she wins the flip, that player copies that spell and chooses new targets for the copy. If he or she loses the flip, counter that spell.
Very few can quit while they're ahead.

Warning, terrible pun incoming.

Allergic Lich (2B)
Creature - Zombie Wizard
3/3
Whenever ~ is dealt combat damage by a green permanent or spell, put a -1/-1 counter on ~.
He keeps his soul in an anaphylactery.

How can a spell deal combat damage?

Also, 3 Mana for a 3/3 with a downside seems pretty weak.

edited 29th Aug '15 7:19:50 AM by LeChuck4

Trade? - 3UU
Sorcery
Choose target nonland permanent you control and target nonland permanent an opponent controls. That opponent may exchange control of both permanents. If they do not, you may untap up to five lands.
Buyback {U}
Merfolk traders are notorious for their persistence.

Exact Vengeance (W/B)
Instant
Destroy target creature that dealt damage to you or had one of its abilities target you this turn.
By us, the mighty, no slight, nor injury, shall be endured without delivering equal or greater payment in return.

Genetic Rending 1RR
Instant
Genetic Rending deals 2 damage to target creature for each creature type it has.

Primordial Order 2WG
Enchantment
Creatures have protection from converted mana costs lower than their converted mana costs.

edited 1st Sep '15 2:14:56 AM by ImperialSunlight

Eldrazi Tender 2G
Creature - Eldrazi
Devoid
Mana abilities of eldrazi you control produce the same amount of mana of the color of your choice instead of colorless mana.
Some eldrazi merely consume all they see, without thought. Others seem to react differently to different kinds of mana, consuming these delicacies as they convulse in mad fervor.
3/4

edited 2nd Sep '15 9:37:24 AM by ImperialSunlight

Ompath, Locus of Sorrows - 3BBB
Legendary Creature - Elemental
Black mana doesn't empty from your mana pool as steps and phases end.
During each upkeep, sacrifice a creature. If you cannot, sacrifice ~ and empty your mana pool.
Creatures your opponents control get -X/-X, where X is half the amount of mana in your mana pool, rounded down.
1/1
It gathers from the fading calm.

Despair Moss - 2BB
Creature - Plant
Defender
~ gets +0/+X, where X is the number of Swamps you control.
0/2
Despair claws at the ankles of all who wade through the bog.

edited 2nd Sep '15 10:19:40 AM by kagescorpionakki