Expanded mind is a useless mastery - it only goes off of base mana (which for Heim is 1410). That means for 4 mastery points, he gets 70 mana at level 18. Which isn't worth it at all. Better to go expanded mind and level faster, so that your turrets and rockets are stronger, quicker. Also, you put a point into rockets first - I've found while maining Heim that if I put 1 point in turrets first, I reach level two more quickly then if I put a point in rockets. Your milage might vary. I'll have to try your build!

Please Vote if you like, but try the build before you dis it ;P