Dagurtheone, if your still having trouble in it, for 12, the only thing you gotta do for those two is go in the booster tube by number 4 straight into the spike under 1, and for 13 just go from the celling straight into the spike pit without hitting any boosters or floor tiles along the way.
I've seen people asking how to beat level 16 in the tower. First, you want to go to the left, fall down two blocks, phase through the green laser, fall down one more block, then back onto the platforms without activating the two pink boxes. Then, from underneath the second pink box, you want to go right, fall down two blocks, left, and then down, and that should get you through the green box without it activating and onto the platform just above the third pink box. From there, go right, fall down four blocks, go up, fall down two blocks, then go left, and that should get you under the final pink block without it activating. From there, just collect the shield, and spam up to victory! Hope this helps!
Also, sorry for my first attempt at this. I messed up my thoughts and said the wrong thing.
I've seen people asking how to beat level 16 in the tower. First, you want to go to the left, fall down two blocks, phase through the green laser, fall down one more block, then back onto the platforms without activating the two pink boxes. Then, from underneath the second pink box, you want to go right, fall down two blocks, left, and then down, and that should get you through the green box without it activating and onto the platform just above the third pink box. From there, go left, fall down one block, warp up, fall down two blocks, and then left, and that should get you under the final pink block without it activating. From there, just collect the shield, and spam up to victory! Hope this helps!
 "Achievement Unlocked"){kind=icon}
 "Warper"){kind=icon}