Here is a casual deck I've been working on lately. It's based on cheap creatures with interesting come into play abilities and Crystal Shard for recursion and card advantage. Survival of the Fittest adds redundancy to the deck, as well as a tutor for utility critters.
It is meant to be a Control deck.
// LANDS -- 22
1 Island
1 Swamp
3 Polluted Delta
4 Bayou
4 Mishra's Factory
4 Tropical Island
5 Forest
// MANA DOODS -- 8
4 Birds of Paradise
4 Wood Elves
// ENGINE -- 9
4 Crystal Shard
4 Survival of the Fittest
1 Squee, Goblin Nabob
// TOOLS -- 21
4 Eternal Witness
4 Man-o'-War
4 Ravenous Rats
4 Wall of Blossoms
1 Triskelion
1 Bone Shredder
1 Spike Feeder
1 Spike Weaver
1 Spike Hatcher
The early game is used to settle a strong mana base. Birds of Paradise and Wood Elves are used for these purpose. Your main goal is to survive until you can reach 7 manas in order to cast Spike Hatcher. Crystal Shard allows you to use the Wood Elves ability many times, so going to 7 manas is not difficult even with only 22 lands in the deck.
Man-o'-war and Wall of Blossoms are used for critter control in the early game, by slowing the opponent's tempo. Ravenous Rats is also a nice tool for this purpose, since you can chump block without losing card advantage. Once you have Crystal Shard in play, things will become easier since you can bounce your dudes with damage on the stack. Man-o'-war provides a reusable bounce and Wall of Blossoms turns into a sweet (albeit expensive) draw engine. If you also manage to get Survival of the Fittest out, then Bone Shredder becomes really strong since you have access to a Terror effect per turn for the cheap price of



. The two smallest Spikes also fit in this game plan. I'm only using one of each because I don't have many slots left for utility dudes, and they can be recurred with Eternal Witness or Crystal Shard if needed (to refill the counters).
Eternal Witness is also a nice card advantage engine, but is probably too expensive for tempo issues. It will be used for recurring lost creatures or a destroyed Crystal Shard / Survival of the Fittest. The synergy with Crystal Shard is also obvious. Eternal Witness is the reason I'm not using Genesis in the deck.
Triskelion and Spike Hatcher are the real win conditions of the deck. Spike Hatcher is a solid 6/6 body with regeneration abilities, and the synergy with Triskelion is obvious. If you manage to get both of these into play along with a Crystal Shard, just move all the Hatcher's counters but one on the Triskelion and bounce the Hatcher into your hand. This will give you an arbitrary large Triskelion.