I don't see how it's possible to do the rifle speed challenge. You have 5 bullets to hit 8 targets. You must reload in order to do it. Firing of 5 bullets as fast as you can and reloading takes 3 seconds. You're supposed to get it done in 2.
Just beat all the levels. Don't worry about how many shots you take, just get at least bronze. You'll get be able to use super bombs as a reward. Then, if you want, go back and do the levels that you didn't get gold on. It will be much easier with better bombs.
Too easy. I got to about 600 kills in survival mode and I just quit after that. I wasn't getting hit at all and I was only getting stronger, so since no new enemies would be showing up, there's no real point to continue.
Got the 2k, but not gonna bother with the 5k for now. The only real tip I can think of is, don't try to avoid the little box things all the time. Only jump over the ones that you're sure you can make it all the way over. Hitting them rarely slows you down significantly enough to make you fail your jump.
Just spread out as fast as you can into empty cells. Even if you're using a cell with 10 little dudes in it, use it to get to another cell. Upgrade reproduction as high as possible. Agility is useless and speed isn't necessary. I beat the whole game with speed and agility at zero.
How to get 20 million in one game: DON'T kill a single thing at the beginning. Just circle them over and over and let more build up. The beginning bots are so damn easy to dodge, you could do it for ever without getting hit. I let them build up for about 5 minutes and then I fire a small burst and they have a huge chain reaction, killing them all. You should have a score multiplier over 2000 and hp above one million after that. The best part is that this game projects you forward based on how many kills you get. So when you get this massive amount of kills at once, you just end up straight at the boss. You don't need to worry about getting hit (you have ONE MILLION health, lol). Just sit there and kill him. If you want a higher score, you could always circle the beginning nubs for longer, but that gets boring.
I went up to 100k feet and then used my 4 boost jets and then used up all my jets moving left. After that I left for a couple hours and when I came back this is what I found: Run time: 1:41:55.50, Highest elevation: 120961 feet, Money collected: $10,108.25, Total Money: $747,683,513.2.
http://s996.photobucket.com/albums/af83/underscoremp/?action=view¤t=lolgsg.jpg