21 is deceptively easy. 3 squirts and 1 swarm in the middle. Set up the maze so teh top group goes to the left entrance, and they all go high around the middle. You can juggle if you need with 1 tower by the top entrance and by the right exit.
Best way to get above level 50 is to advance mercilessly. Just get going and advance en masse between waves (a scout helps to watch the timers). Once you can get BARs on all your soldiers and heroism to keep them at 200 hps. (Also, dont have more than 7 soliders, minimizes artillery and bombs). You cant effectively kill tanks, so just kill everything and advance.. tanks only count as 1 left behind. When you want to bunker down (around 90 to prep for 100), bunkers, trenches and french bullet shields and hope for the best.
Finally beat it.
If you are having troubles with keys not working or sticking.. you are probably using IE. There is an API bug in the Flash plug-in for IE, switch to Firefox and it will work fine.
Swing is 2 well timed cuts. Diagonal cut about 1/3 off the block letting it slide off the ramp. Then quickly diag cut as much as you can on the block again, letting it slide off. The ball should hopefull hit the star before rolling back to the exit.
Hard Badge:
Upgrade all, have 3 groupies.
Launch and start a handstand, point the cart straight up while holding the stand, once you hit the apex of the flight (should be seeing stars if you did it right, really high up), complete the flip, release the handstand, get the 1800 pts.
4/5
Solid game, tho i cant give 5/5 because its a sequal that didnt really add anything special. Its a good game, one that I will play alot, but i reserve my 5's for the really really good ones or very original ones (like the first Music Catch).
3/5
Deduction for never need to upgrade base (pointless to have others if you dont ever have to use them)
Deduction for Existing bugs (like the turrets)
infinite point bug still around:
Get a tank, drive it to the top.
Repeat.
You cant lose by leaving enemies behind, only if they actually advance off the bottom. The tank is generally faster than opposing troops because they stop to shoot.
Easy way to get lots of points, you just need a rock solid defence when you stop, or once Col. rank, you can just die and then start with tons with Proper Planning special.