User blog comment:Leyrann/New Summoner Spell?/@comment-5022584-20120818172211

I can see why you thought about this. A one-use-per-game spll could be nice.

Pros:

Unique spell idea.

The decision of where and when is crucial and has to be carefully chosen.

Cons:

Can decide a game in a single spell. Which would make the whole laning phase irrelevant.

Imagine getting in a team fight and simply dying at the beginning of it. Would drain a lot of fun and suspense out of those team fights.

Also, if every member of a team takes it and wait around 30 minutes. Auto-ace and push to win.