Quote Originally Posted by Left6 View Post
You have to consider that these games take place in different periods of time which would explain the strength however, I don't really think this is a 'story' decision.
There's only a few months difference in between Halo 3 and Reach, and only mere days between Reach and Halo 1. And you can't explain the difference between Hunters the same way you can explain there not being Brutes in Halo 1. It's merely a gameplay decision.