The interesting problem here is that white and green get 2/2s for 1C with an advantage, but blue, red and black should only get a 2/2 for 1C if it has a drawback. Making the drawback and advantage reference each other is an intriguing and fun restriction.

Yeah I wanted this challenge to be a challenge, will be interesting to see what people come up with.

Oh, good question. I hadn't realised when I first saw it. It doesn't fit the terms of the challenge, but it makes me think of something like this: :)

White Knight. 1W. ~'s power is equal to the number of plains you control, and its toughness is equal to the number of forests you control.
Green Knight. 1G. ~'s power is equal to the number of plains you control, and its toughness is equal to the number of forests you control.
Cerulean Knight. 1U. ~'s power is equal to the number of plains you control, and its toughness is equal to the number of forests you control.
Yellow Knight. 1R. ~'s power is equal to the number of plains you control, and its toughness is equal to the number of forests you control.
Grey Knight. 1B. ~'s power is equal to the number of plains you control, and its toughness is equal to the number of forests you control.

Hahaha!

OK, this one was harder than I thought - the restriction of not being allowed to use any Keyword abilities is quite restrictive. Anyway, here's what I came up with:
(((Brimstone Battlemage))), (((Ragewild Battlemage))), (((Serenity Battlemage))), (((Mindcloud Battlemage))), (((Mindrot Battlemage))).
A cycle of Battlemages with enemy-colour activated abilities (and named after the abilities - which is why some names may seem strange given their colours).
Not sure if they are in anyway balanced within themselves but hopefully they are all interesting.
The cost to activate the abilities can be a drawback whereas the abilities themselves are advantages that aren't usually available to the parent colour (I hope).

I'll be tackling this tomorrow... I'm to tired for now, but I do love cycles.

Camruth: Fun cycle; reminiscent of Ana Battlemage in the Planar Chaos alternate universe. But if Wizards were printing it it'd have to be at 2C rather than 1C (like the Sunscape Battlemage cycle and the Bant Battlemage cycle), because red, blue and black just don't get a 2/2 for 1C without a strict drawback. A 2/2 with some ability that's remarkably fiddly to activate doesn't count, because it can still be a Runeclaw Bear. It has to be something that applies even if you only ever use it to attack or block for 2.

I may have made this one a bit too challenging. So I have modified it to make it all 2/2 creatures with a maximum CMC of - one of each colour still * Casting cost has the be the same on the entire cycle.

Ha! I got there, but I admit, that was a challenge. Even more so that they all had to be mechanically tied together. (and still, I kind of cheated, since keyword abilities were involved in some way...) Odyssey had a cycle of hounds that all do this, but the only connecting factor between those cards was that they had 5 different ways to say 'dog' (Mad Dog, Wild Mongrel et. al).

Still, I don't think there's anything wrong with creating a very difficult challenge, then failing to be able to follow up on it yourself. I'd rather push people to try to create absurd things, then let them fall back on comfortable and easy. B-)

EDIT by Alex: The cards are Interim Ambassador, Bogle Ambassador, Despised Ambassador, Trumpeted Ambassador, Flighty Ambassador.

Alex: Huh, you're right. I hadn't realised it was so strict. There are plenty of CC and DD 2/2s with upside and of 1C 2/1 with upside, but no actual grizzly bears, even at rare.

In fact, it's interesting that W and G get better than grizzly bears, and B, R, U and A get worse than grizzly bears, but no colour only just gets grizzly bears any more. Now I feel more enamoured of grizzly bears (even if in a constructed format you can find a 2CMC 2/2 if you need).

Camruth: Yeah, I think it's definitely interesting, even if it its hard to actually fulfil.

Bah, you made it easier? where's the fun in that? :) No, it's fair enough, this way there's a lot more choice.

But I decided to go for the original harder version anyway :P So behold: Lunging Evotan, Lurking Evotan, Leering Evotan, Lagging Evotan, Looming Evotan. The idea is that when they're fighting their own kind, they're just vanilla 2/2s. But when they fight something else, it's very different :)

I'd imagine whatever set had these would also be an artifact Evotan (a 2/2 for , probably vanilla like Stonework Puma), and perhaps another cycle of them at 3/3 for 3C at uncommon. That should provide enough of them that their interactions would get noticed in Limited, and perhaps people might start sideboarding in some to fight against the white or green (or blue) ones, or sideboarding some out against the red or black ones :)

Ha! I've just seem jmgariepy's ones (he didn't provide links), and his and my red ones are virtually identical :) Given which, it's quite pleasing that our other four are so different!

Alex: Interesting cards and well done. I could see an Evotan "Lord" that blanks text boxes of other Evotan, negating the drawbacks of some and advantages of others.
Jmgariepy: Also cool cards, funny that you both went the "blocks or is blocking" path - Great minds and all...:)

Here is my contribution:
­Aura Feeder, Gear Feeder, Crypt Feeder, Rage Feeder, Terra Feeder.
Hopefully they are OK as I'm still kinda new at this.

@Darkheart: They seem a perfectly reasonable entry to the challenge! I hadn't thought of going that route - the same kind of drawback with all of them, just a stronger circumventing ability for green and white.

Darkheart: Yeah, that's a nice twist. I was looking for something similar, with a drawback that was not always a drawback, but didn't think of anything and "does not untap. Untap if you..." is a good choice.

Oh, it didn't occur to me to list my 5 cards here for some reason. They're Interim Ambassador, Bogle Ambassador, Despised Ambassador, Trumpeted Ambassador and Flighty Ambassador.

Nice cycle, Alex. I like how these guys ignore the rest of the game when they're just fighting each other. Feels like the flavor for these could be very strong, like a bunch of creatures all cut from the same material, whose powers don't work on each other. Cyclops versus Havok and all that.

Darkheart's entry looks good, too, but, they are a little harsh. I think they should all get the +1/+1 bonus when you untap them, not just the white and green one. I figure it's okay that they all have the same power level if it is hard to pin down just how powerful that is...

I changed them slightly, Red & Black now get +1/+0 and Blue +0/+1

I liked it when the red one got +1/-1. You could always do it at the opponent's end step if you wanted to attack with it as a 2/2 rather than a 3/1.

I finished my cycle and then realized that I used a keyword... so here's what I came up with, but I guess I'll be trying again. lol ­Soul Wanderer, River Wanderer, Rot Wanderer, Rage Wanderer, and Loam Wanderer.

Okay, here is my (hopefully better) attempt. I hope the connection is clear enough. Tenacious Knight, Unwilling Assistant, Resentful Mercenary, Bloodhunger Ogre, and Indomitable Warrior.

OK Here is my attempt, each card is functionally identical just colour/creature type(s) differ:
Twinned Kithkin, Twinned Illusion, Twinned Zombie, Twinned Goblin & Twinned Wolf.
They are not AMAZING cards but for a 1 CMC 2/2 common creature they are pretty simple and an easy way to introduce new players to the concept of token creatures.

Just when you think you understand design guidelines, wizards prints a common 1B 2/2 zombie. Referred to on twitter as a "grisly bear" :)

Finally figured out mine... Argent Priest Ertek Deolater Haddragh Cleric Urk Monk Targan Shaman