Coiling Oracle
 
This card is very suitably Simic - subtle, sneaky, and serpentine. It's easy not to notice the advantage you get from little extra effects like this piling up over time, and even easier not to notice that if you get a land, it doesn't come into play tapped unless its own game text specifies. It's usually a stronger effect in a vacuum than only drawing a card, as with Elvish Visionary, and an excellent reason for tribal decks with either snakes or elves to go into blue (and one of the craziest combinations of tribes ever!).
 
Constructed: 4/5
Casual: 4/5
Limited: 4/5
Multiplayer: 4/5
EDH/Commander: 4/5

Coiling Oracle (4/3)
 
One of the more unusual and beloved cards from Dissension, Coiling Oracle is basically a 1/1 cantrip with a lot of upside. You get to either put another land onto the battlefield or draw a card, leaving a 1/1 behind.
 
Two colors is sometimes a bit of a chore to ask for on turn 2, and this has the most effectiveness in the early game, when you can use mana acceleration and a 1/1 isn’t a speedbump. If you're in Bant colors or just in Simic colors, though (or some other 3-color combo involving green and blue), the little mutant freak might be a worthwhile inclusion.
 
Constructed: 4.5
Casual: 5
Limited: 5
Multiplayer: 3
Commander: 3.5