The problem with Mirror Image as compared to other Clones is there's a higher chance of it being a dead card when your board is empty. What Elvish Hydromancer does here is placing the clone as a kicker effect so worst comes to worst, you can just copy the Hydromancer if none of your bombs are available.
I like this less than most of the other uncommon kicker cards spoiled, simply because the non-kicker version is rather weak. I'd still be happy to play this in a green/blue deck, though. Nice art too!
The problem with Mirror Image as compared to other Clones is there's a higher chance of it being a dead card when your board is empty. What Elvish Hydromancer does here is placing the clone as a kicker effect so worst comes to worst, you can just copy the Hydromancer if none of your bombs are available.
Source: 4Gamers
If I'm not mistaken, no it won't go infinite as the token copy entering the battlefield wasn't kicked.