Seems like everyone did well regardless of their build.
But try pure Speed + Strength. I beat every level in literally 20 seconds. (You just have to be fast with the mouse :D)
Like others have said, it's a bit too easy. Maybe you could add different armor classes, to force players to diversify. For example, Riflemen have piercing rounds, dealing 150% damage to armored targets but deal their normal low damage to everything else. Or shotguns deal huge damage to big slow units but little to faster enemies. Icons displaying unit's damage type would be awesome. Information and statistics in strategy games is a must.
Numbers should be added to the upgrades and unit stats, most people who play defense games are definitely number geeks.
Speed control would be a plus, Riflemen need a buff, maybe extra long range?
Range and damage towers should also get their buffs increased as they are upgraded.
Easy way to beat motherships:
Build a network of relays up and around them once they stop to attack your base, then quickly build lasers around them. Rebuild relays as they try to take down your network
Not bad... Like others have mentioned, enemies can spawn on top of you, healing costs too much, and also Pips shouldn't despawn... They are very rewarding to collect, They should be available forever (or at least longer). The diffuculty jump that people have complained about I just don't mind that much. It made the game EXCITING! It was a rush to try and survive.
7/10
It's got potential
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