This is a mono blue deck centered around using Training Grounds and Molten-Tail Masticore to control the board and eventually use the Masticore as a win condition. I am looking for advice on the mainboard and sideboard. This is also my first deck that I have posted here.

Training Grounds can decrease the casting cost of the Molten-Tail Masticore 's ability down to 1 if there are two out on the field. Usually there is only one though, which yields something like 2 mana for 4 damage. If you compare this to the Heartless Summoning, Perilous Myr, and Havengul Lich combo, it's quite similar (1 mana for 2 damage). Both require three cards, and the only downside about using the Molten-Tail Masticore is that your graveyard could run out of creatures, though playtesting shows that this is going to be highly unlikely unless your opponent has a good amount of life gain. Cards like Glassdust Hulk , Enclave Cryptologist, and Architects of Will all help fill up your graveyard.

The deck doesn't use any counter magic, because I wanted to have as much creaures as possible to feed the Molten-Tail Masticore . The Spellskites effectively function to protect your other creatures and particularly the Molten-Tail Masticore against removal spells. Even if your creatures get countered or killed, they can be exiled and used to your advantage. Since the Molten-Tail Masticore can be regenerated, Day of Judgement isn't really that scary. It will kill off all your other creatures though, so use his ability!

I added Ludevic's Test Subject as an alternate way to win. It essentially functions as a defense unit, but when you get out Training Grounds, you can tap five mana and turn it into a 13/13 really quickly.

Please help me with some suggestions on how I can improve this deck! I still need to configure a sideboard!