For the love of god, add some keyboard shortcuts! The majority of the game is played with the keyboard; so why do I have to move the mouse to click a button after each level or when I want to restart. So frustrating.
Upgrade path: Final Pistol > Final SMG > Final MG. Upgrade each to full before purchasing the next. Don't bother with any other weapons. The last 25 levels or so are a cakewalk this way.
I've got a complaint about the poor optimization of this game. It gets very resource-intensive in the later levels, which slows the game to a crawl and makes the last badge more a test of patience than a test of skill.
I easily beat the hard badge, here's how:
65 gunners, 30 repairers, full wall, fully upgraded laser turret, shield, and missile launcher.
Fully upgrade the orbital laser and just spam it on the tanks and mechs.
The game never gets harder after about level 30.
Are there any upgrades after the pistols? I played until a height of 110 with no variation in difficulty or upgrades. It would be nice to be able to earn more grenades and different weapons. A boss wave every 50 feet or so would liven things up, as well.
Also, bad placement of the link on the game screen. A top corner would be a better spot, as you never have to click there.
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