Kind of powerful for a common. A 3/4 isn't something you would normally seen on turn two. I would consider making it a 2/2 or a 1/3.

I like what you're trying to do with Curve. The problem with this implementation is that you're incentivizing players to do something that they would be doing anyway - playing their spells on the optimal turn. Rather than providing interesting decisions, it removes interesting decisions, because players will have less reason to make alternative choices with playing out there curve.

Yes, it seems more like you'd want to reward players for playing differently. Also, it's unlikely most people are going to want to count their turns up to turn 5.

Curve seems to keep getting the same response. I find it more funny than anythings else. I definitely understand BD and Link's response, but I don't feel like adding to what's probably a dead subject for you.

I will, however, point out that creatures like this are particularly Spiky. Better on round two, and continues to stay that way throughout the game is probably fine on one or two creatures, but I, personally, wouldn't pull that trick too often. I like curve when it gives me a noticeable effect, then goes away. In this instance, for example, gaining 4 life when the creature comes into play may make a better incentive for curve. Why? Well, you don't feel bad when you play this creature on round 8 because it's smaller. It was always going to be a 2/3... but playing it on turn 2 gave you a bonus.