Original Halo CE greenthumb is not the same in MCC. B should be Zoom in but now its Right bumper. I know green thumb has a disadvantage and you guys just made it worse. i have played thousands of hours over the last 10 years and this set up is embedded into my head. I will have to return this game and not be able to continue playing halo if this is not fixed. The only control type i would be willing to switch to is if you could make left bumper the zoom function. The disadvantage with greenthumb is having to remove you thumb from the right thumb stick to zoom back in after being shot. I am very fast and very good with this, and my entire game play is around this obvious disadvantage. Please fix the original green thumb, and think about adding a control option to make the left bumper zoom, that way you do not have to remove either you trigger finger or your reticle control (right thumb) to zoom back in.