The Cycle of Cards Game

Sure thing.

Your next card is Saltskitter. I think there's several ways to spin different parts of this creature's ability into different colors, so I'm curious to see what you all will make. Good luck!

Spellslither 
Creature -- Snake
Whenever you cast a spell on another player's turn, exile Spellslither. Return Spellslither to the battlefield under its owner’s control at the beginning of the next end step.
2/3

Underbrush Smasher
Creature - Wurm
Whenever another creature enters the battlefield, CARDNAME gains trample until end of turn.
4/4

ZephyrPhantom I think this could get judged.

inferno390 - Missing P/T. Otherwise I think this is a good spin on the idea, there are a lot of payoffs for ETB-ing out there and this makes you want to do an intuitively red thing to start the ball rolling for those payoffs. I think you could possibly even extend it to players but as is it's a great design - honestly kind of bummed that you forgot the P/T because it really cripples an otherwise cool common.

@jamesbrafin - As someone who likes the idea of manipulating when and how the creature gets exiled I think your choice of a condition is smart. I only wish it was something more like a 4 3/3 or even a 4 3/4 that could be used as a bad draft finisher of sorts.

viriss - Interesting how you chose to tweak the protection effect instead of the trigger. It does help it dodge creature removal and fuels Improvise so I think there is merit in playing with the effect in this form. You also seem to have observed that this also works as a sort of drawback that prevents you from casting creatures on main phase 1, which while small is not an insignificant drawback. While I agree I'm not sure if this is close enough to the cycle anymore, I think that's offset by high effort and a set-ready design.

gamma3 - While this is a perfectly good green common (set-ready, in fact) I don't think I agree with this as being faithful to the cycle. As its competitors have noted, Saltskitter's trigger functions as both a protective effect and a drawback to make you not play your cards at incorrect times. Granting trample doesn't really do either - protection or hexproof would've been more fitting.

Flo00 - Same issue as gamma here - the design is perfectly good and set-ready but I feel like regardless of whether you are editing the trigger or the result, it doesn't feel right for members of the cycle to not protect themselves when something is played.

1st: viriss
2nd: inferno390 - Even despite the lack of P/T this probably would create a lot of interesting strategy decisions in limited.

Lol, I'm not sure I'm doing this correctly, but your next card is Sunforger.

Just FYI, Sunforger was already part of a loose cycle already.

Spellsaver
Artifact — Equipment
Equipped creature gets +4/+0
, Unattach ~: You may cast target instant or sorcery card from your graveyard. If that card would be put into your graveyard this turn, exile it instead. (You still pay all costs)
Equip

Oh, I love cards with all the knobs! So fun to tamper with!

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Storm Hammer 

Artifact - Equipment
Equipped creature gets +3/+1

, Unattach Storm Hammer: The next time you cast an red or blue instant or sorcery this turn, copy that spell for each other spell you cast before it this turn.

Equip 

viriss, could we convince you to judge?

Thanks viriss! One day I’ll remember to add rarity.
And speaking of rarity, let’s see some big splashy mythics to go with Craterhoof Behemoth!

It that Shatters Skies
Creature - Eldrazi Horror
Protection from colored creatures
When ~ enters the battlefield, create X basic land tokens named Wastes with ": Add .", where X is the number of Eldrazi and Horrors you control.
5/5

I’ll give this another day or two before judging