Thanks for this video, this should prove very useful.
Looking at it I think he made it a bit harder for himself than I found myself on Stage 1 travelling through the base. It's the section with the 2 orange rocket firing bastards that looks to be the bit that makes or breaks this achievement. I think a fair degree of skill and luck will be needed to get through that bit.
Stage 2 in comparison I reckon is a lot easier. On stage 2 at the bit just before you fly through a narrower section just before the snake first appears you hit a checkpoint. So if you can get to where it narrows and you die, its not so tough as then you have a clean run through to the boss fight. With the stage 2 boss I'm wondering if you can just concentrate on the snake only, so if you don't destroy the boss the level should end anyway. This may still award the achievement without having to risk sitting on top of the boss like he does in the video?
Regarding the continuing question, good point. I guess will have to try it out and see. In the process of trying I suppose you can refine your technique!!
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100% Arcade Completed: 107
Currently working on: Lego LOTR