Rederdex has just submitted some Achievement Flag Info for
Portal Achievements:
Rederdex said:
The Camera Shy achievement in Portal worth 21 pointsDetach security cameras from the walls."The flag is not applicable to achievements that can be reattempted by using a level select option"
You still have to play through mostly the whole game again, but you can select just the levels that you actually need for the achievement, making this a non-missable achievement
The Friendly Fire achievement in Portal worth 11 pointsKnock down a turret with another turret."The flag is not applicable to achievements that can be reattempted by using a level select option"
You can just select a level with 2 turrets inside of it without any problem, making this a non-missable achievement
"The flag is not applicable to achievements that can be reattempted by using a level select option"
You still have to play through mostly the whole game again, but you can select just the levels that you actually need for the achievement, making this a non-missable achievement