­:)

I'd be tempted to either (a) make this a mana creature rather than a land or (b) just give it ninjitsu and have it be an implicit tweak to the rules that "attacking" doesn't do anything for non creatures.

I'm not sure if I'd play it. The ability to have mana acceleration on a land is quite useful, as it improves your mana a bit without wasting a spell slot. But OTOH, this never actually increases the mana available above the number of cards you draw ("put a land from your hand into play" cards are never as strong as you'd wish), and furthermore, you want this when you're trying to accelerate, in which case you don't normally want to be attacking and bouncing creatures. So it's probably actually costed fairly fairly.

It's probably most interesting if it can be paired with tricks (to rescure an attacker from a burn spell, to trigger landfall, etc) which means it's interesting :)

While I appreciate that you noticed that this was mana acceleration, and therefore made it green, this doesn't feel very green. Green doesn't need to play tricks to get its lands on the battlefield. It just makes creature and land. White, or Blue seem, to me, more likely to trade an attacking creature for tempo advantage.