To get two achievements, go play 2 player on any maps on Annex and make sure Player 1 or Player 2 stay in the circle for the Nub Pwn3r. Do this 20 times. For the Inconceivable make sure that Player 1 or Player 2 go to the circle first then the other player goes to the second circle then the same player goes to the third one but before it to countdown finish (for example before 120, stop at 115-119) then the other player goes to finish the circle then to the last circle to the round. Do this also 20 times.