The Grenade Launcher has a ridiculous amount of ammo per clip... like 12 shots or so. This means you can spam-fire it the entire way to the end without running out of ammo. Which is the best use for it, due to the delay on the explosion.
Seems like the best of both worlds to me, I'm glad Kongregate is now offering them. You want to support the dev or get free stuff? Watch ads. You hate ads? Well don't. Way better than the old regular "interruption" ads.
Prioritize speed for all characters, especially when you're making choices. More speed means you get to act more, which boosts all capabilities significantly.
Finish Level 19 with just gatling? How about every level up to it too? That's what I did. Levels 15 and 16 were frustrating but I grinded up some cash from them.
Arrows overpenetrate in this game. The bow is already an incredibly useful weapon, and you can get more use out of each shot if you aim through enemies to hit multiple with one arrow. It makes eliminating hordes so much easier. (Dunno if that works in any of the earlier games though.)
I've found a consistent late-game 10-day 200000 story mode victory method. Day 1: Omega Penguin and RC helicopter. Day 3-4: Buy Ejector Seat. Day 5-6: Buy Rocket Kit. Day 7: Buy Superhero Costume. Day 8-9: Buy Spearhead level 3, Spin Booster, and at least 1 Dubstep Drive. This doesn't even require bonus levels to work. Expect to have 3-4 Dubstep Drives at level 1-2, a base level spin booster, and if you upgraded the Spearhead to the max, fins at level 5.
What I think this game needs is not more colors, but an option to choose the colors each box uses. So, box one could be blue, box two could be sky blue, box three could be aqua, and box four could be teal. But no more than 4 colors at any one time.
A few tips:
The pistol is actually a VERY good weapon simply because it doesn't run out of ammo. And if you actually repeatedly press the spacebar, you can fire it as fast as you can press space. Which can easily be as fast as the Uzi or Assault Rifle.
Second Tip: Assign your main weapon to the letter Q, then assign the other weapons you like to the nearby keys. This makes weapon switching a lot easier.
Third tip: The Shotgun and the Bazooka are both good cloud-clearing weapons. Fire the shotgun at groups of close enemies and fire the Bazooka at groups of (preferably far) enemies. Only fire the bazooka once at a group of targets, more than once is overkill.
Finally, when Sarah asks for a weapon, don't worry about losing one of your own. You'll still have the weapons you earned before afterwards.
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Seems like the best of both worlds to me, I'm glad Kongregate is now offering them. You want to support the dev or get free stuff? Watch ads. You hate ads? Well don't. Way better than the old regular "interruption" ads.