Tip: in lvl 15 you have a boss again. that is a green laserblade shooting thing. you need to shoot at his laser blades he shoots away so they bounce back and after 3 times he will die.
And for the people who don't know how to get a combo is not hard. There are two ways. easy and hard btw
first you need to know which towers you need to put together to form a combo. Here is a link: http://onslaught.playr.co.uk/about.combos.html
1.If you want to make a landmine, you need to put 2 blue turrets next to eachother. fully upgrade both damage of the turrets and done.
2.The harder way is to get the combonly. since you only can get it by defeating wave 150-200+ i would not recommend you to use this method but its handy to know. When you have unlocked it you need to build it. And we want to make a landmine so we need to put 2 blue turrets around the combonly and fully upgrade the damage. Then you will see that the combonly will have a blue glow. Click on it and you have a blue turret that only shoots mines :D.
I hope it has helped!
tip if you want to get extreme!!
Go to maptools, then map editor and make a map that is like a square and overlap the squares. Make about 10 sqaures on eachother. Then you can easily get to wave 200.
Absolutely love the fifth boss. Unlike the other shooter games, you can't simply flunk the boss by ramping up your damage output. You actually need to learn how to dodge the attack patterns. Kong needs harder top down shooters.
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