As you can see, in the title, this is a warp world deck. I chose the colors because they have the strongest ETB abilities and for the ability to return warp world to your hand. For starters, I'll go ahead and post the deck list of the latest and below that will have explanations for the card choices.

Lands -
3 Plains
4 Mountains
4 Islands
2 Jungle Shrine
2 Arcane Sanctum
2 Seaside Citadel
3 Mystic Monastery
1 Azorius Guildgate
1 Boros Guildgate
2 Izzet Guildgate

Land Base explaination
Obviously, the dual color lands aren't important if they are trilands or guildgates but I just like the combination and confusing information can affect your opponents way of playing against you. You want to run basics for tempo and to hit Warp World chains

Creatures

3 Wall of Omens
1 Brimaz, King of Oreskos
2 Mentor of the Meek
2 Banisher Priest
2 Attendant Knight
2 Kor Cartographer
1 Captain of the Watch
1 Resolute Archangel
3 Guard Gomazoa
1 Master of Waves
1 Jalira, Master Polymorphist
1 Roil Elemental
1 Goblin Rabblemaster
1 Ogre Battledriver
1 Kozilek, Butcher of Truth
1 Warden of the Eye
1 Inferno Titan

Wall of Omens and Guard Gomazoa - These will help you stall. Wall Cantrips while Gomazoa blocks anything and especially helpful vs flyers because we are particular vulnerable to flyers.
Brimaz and Rabblemaster - These generate tokens basically each turn they are out which are more permanents for Warp World and also give us early game pressure if dropped turn 3.
Mentor of the Meek - Pretty straightforward with all the tokens we make and becomes a real engine late in the game or after a Warp World resolves.
Banisher Priest - Pretty much the decks only pseudo-removal. Moves pesky things out of the way but remember they come back after a warp.
Attendant Knight, Captain of the Watch, Master of Waves - ETB Tokens, straight-forward token producers
Kor Cartographer - Early to mid game ramp, generates 2 for 1s with Warp World
Jalira - 1 Card warp world, helps dig through your deck to make more tokens, get more lands, or draw more cards
Roil Elemental - Off a warp world steals all of your opponent's creatures
Ogre Battledriver - Haste and pump off of warp world or for Brimaz/Rabblemaster tokens to come out hitting harder
Kozilek - Does this really need to be explained? Hit it off a Warp World and feel good
Warden of the Eye - New addition to the deck, replaces the old wizard who is only 1/2. The 3 toughness is great. Allows you to loop Warp Worlds by returning after it resolves
Inferno Titan - Kills small guys, helps close out very quickly on it's own

Spells
1 Time Warp
2 Warp World
2 Planar Cleansing

Time Warp - Because extra turns are fair
Warp World - Keypiece in the deck for big wins
Planar Cleansing - Boardwipes are important when you are stalling trying to get to 8 mana

Artifacts
1 Elixir of Immortality
2 Darksteel Ingot
2 Meteorite
1 Courier's Capsule

Elixir - In case you lose Kozilek and are afraid you will mill out
Darksteel Ingot - Ramp
Meteorite - Ramp with a shock attached, fun to hit off of Warp World when they hit dorks
Capsule - Card draw on a permanent