Its possible to go negative mana. first get enough mana to upgrade a jewel, then buy an orb, then click upgrade, then the gem you want to upgrade and then you can place the orb that you bought, and if you don't have enough mana, it will still be bought.
I just zoomed in. Ctrl+mouse wheel. And i could see perfectly. my complaint is that when i placed a tower near one of the beginning structures, i couldn't select the tower to upgrade it, because I would always select that structure.
Deselect using spacebar or something would be wonderful. I've accidently sent units to attack enemies, when I only wanted to view the intel on them. But other than that, I like this game. 5/5
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