Realy great game. Unique!
If you make a second one you could add special structures and powers to give it that strategy edge like Command and Conquer. Also as QuakeZero27 said get rid of the auto-lock and put it in the options menu to activate and deactivate when you want! 5/5 All round tho.
Wow in my opinion this is ONE of the best tower defence games on any website ive seen! Altho you should add a tower upgrade tree where you start with a basic tower then upgrade to a heavy, fast or equal tower and so on, sorta like bubble tank tower defence!
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