Level 4 isn't exactly easy to explain, you just have to avoid the nitro. The main thing is that you have to go left a lot because you have to much momentum, which is going to throw off your jump.
playr10, the clone is the clone of the main character from the alternate ending, if you wait a bit instead of going directly into the beam of light in the last level you'll get it.
Silo212, and anyone else who is confused: To beat the 'K' level, you need to collect the spikes on the left, then go back to the wall, jump, and press K midair. This shoots a spike that sticks to the wall. You can then jump on the spike and use it as a platform to get over the wall. Hope this helps!
blufrost007: You have to get him to get hit by his own attacks. When this happens, dark colored gems will appear. If you collect these gems, he will take damage. As for the race, either level up your skills until you can beat it, or just buy the skill.
I'm pretty sure the only reason I'm still playing this is because of the funny descriptions and the sense of accomplishment one gets from finding all the party members.
 "My \"Dear\" Boss"){kind=icon}
 "Cat Stretch"){kind=icon}
 "Mitoza"){kind=icon}
 "Invertion"){kind=icon}
 "Thermo"){kind=icon}
 "Recoil 1.3: Noobs Edition"){kind=icon}
 "Depict1"){kind=icon}
 "Loved"){kind=icon}
 "Space is Key Hell"){kind=icon}
 "Upgrade Complete 2"){kind=icon}
 "Space is Key"){kind=icon}
 "My First Quantum Translocator"){kind=icon}
 "Level Up!"){kind=icon}
 "Tanaka's Friendly Adventure"){kind=icon}