Thanks you all for great feedback
I agree with Thalas. It's underpowered. I'd get rid of the delay effect.
The reason for the delay is that you are basically using a future use of the skill. It's not about giving you more, its about getting the most you can when you need it most. I decided to delay rather than just not allow the use of the skill next turn because some skills are related to damage, and this is a card is all about speeding up specialty skills (like devour, Dive, steal, destroy, lobotomize, Queen, mutate) rather than helping out the growing skills (like growth or ablaze). Not that I think they are overpowered, I just don't think they need the help.
It's broken when you combine it with Dive, since you can play more than 1 Time Travel on your diving creature per turn.
http://elementscommunity.org/forum/index.php/topic,10250.0.html
Sure, you can play multiple Time travels. That is the most efficient use, I think, since I don't think delay counters stack. I could make them stack, but I think that having a delay at all is already enough of a drawback.
Dive is the most powerful combination with this card, with 5 TimeTravel cards on 1 elite worm, you would deal 320 damage, and that's ignoring any buffs. I don't see how I can mitigate that though.