@goldenspirit
Rocket Race 2.0: You want a juggernaut for their high health (sure aim is a bit worse, but EXPLOSIONS means it doesn't matter much). Hunt down the weakest enemies (generals and snipers) whilst avoiding high enemies (especially mercenaries since if I remember correctly they have a thingy to reduce explosion damage).
Defection: I posted a video back on page 38, but for some general tips, here are some. Sniper is probably the best class, as their high damage long range (DSR1 is my preferred weapon, but the Intervention and that other super high damage sniper rifle I do not remember work as well), pick overkill as your trait and either wallhack or invisibility as your killstreak. Secondary weapons is bouncing knives, you can spam them to shoot around corners and they still keep overkill damage.
Once the game starts, check for any soldiers that aren't the "Loyal Soldier" to make sure they don't have explosives or sniper rifles, and then head to the middle of the map. Here you want to get a few quick kills and build up overkill, then head to the top. Once you get to the pylon thing on the ramp down to their flag, you wanna stop. Scout out the enemy base and wait for their to be 1-2 enemies left. At this point run down, shooting both on the way, and run back up around the top.
Rinse and repeat this strategy, using stealth before taking the flag or wall hack to build up overkill/protect your flag as you head to the enemy base. Always go up over the top, it's less traveled and you have longer lines of snipe to shoot over. Once you get into late game however (1-2 allies left) just don't worry about defending any more and just go straight up aggression.
A few final pointers for this challenge: snipe from long range, spam knives on the way back, and DO NOT LET AN ALLY GRAB THE FLAG, they will transfer the point when they defect.
Randomania: This is probably the simplest, unless the bug was patched (been a while since I played). Pick a sniper, again with DSR1/otherhighburstsniperrifle. Every time you die, your weapon will reset to your standard weapon until the next randomization, so you have 10 seconds to get a couple free kills. It still takes a bit o' luck, but this is the easiest method to complete it imo.
p.s. If you have anymore questions, just tag me @Jacen96 and I'll come back to answer them. Also, check out Reton8's indepth guide located here, it has information by a variety of users covering most aspects of the game.
~~~Darth Caedus