Facts about onslaught that might be useful to others...
The nuke has instant kill until around wave 130
If you dont have much to do and want it to go faster you can decrease wave spacing (10sec-20sec), switch on "send next wave immediately"(automaticly sends next wave when every creep is killed) or increase the time factor (50%-200%)
There are many combos you can make by placing different turrets near each other and increasing the damage to max (a list of combos here http://onslaught.playr.co.uk/about.combos.html)(press "c" to toggle between show or hide combo-range)
You can move turrets with "m" but it costs 500$
Black holes are owerpowered but does not give money or kills
I got 1568 kills on extreme but somehow I still did'nt get any badge, which makes me angry
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