Good game, but not as much of a storyline as the others and can get quite laggy. Also, leveling up characters takes ages - but here are a few tips:
Buy Rocket Launchers for Engineers and Mercenaries
Use Sniper Rifles for Snipers and Gunslingers
If you see a perfect or customised weapon in the shop, buy it. If there are no good weapons and no blueprints to build, then spend all your money on the slot machine, it's worth it. I have completed this game twice on NotDoppler and I've found that for the last level, don't use the AI, just go as your captain, with a grenade launcher. Get to the highest position on the map, Street, where you can bombard Mike and Justin with the grenades. Also, don't recruit too many heroes, dismiss one if you have too many of that class. Enjoy! :)
If you hold down the lLearn to fly 3 logo in the title screen for 5 seconds then you will unlock sandbox, payload and classic mode. Also, to get into space (200,000ft) get the Jet body, Russian Roulette and 3 Sonic bursts, then upgrade them and when you get a killer shot you will get into space. The penguins that pop up in the store are Easter Eggs, click on them to see where they lead you.
Guys, to unlock sandbox, classic and payload mode, in the title screen hold the 'Learn to Fly 3' title/logo for about 5 seconds and it unlocks all the modes. Please + so everyone can see it
Sure, we want YOU to get us into space. Oh, you say £5 Billion. Nah, you're just launching a hedgehog. Tell you what: we'll give you $50! Right, now what was that about the new limo for $300,000
74 unlocks, then won the beating the baddies badge. WOW! Straight up to 93 unlocks and the hard badge + loads of riders. Totally worth spending my time on.
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You also skipp all tutorials if you use this little cheat so not recommended for first time players.