Went out and looked for more prototypes, didn’t find as many, but I do have more info to make up for it. The first two pictures are a unreleased Spirit prototype, very surprising to know it would’ve came out in 2012, it was one of the 3 sets in the halo fest vote, the other two being the Forerunner structure, (found in Unreleased sets and prototypes, from March 28th of this year) and the Sabre. (pics 3&4) The prototype had 3 grunts, a jackal, and an Elite ultra. The most noticeable aspect is it being the Bungie Era design, when back in 2016, it was based off 343’s spirit. The YSD-1000 Sabre seemed to have been only about the ship itself, before being expanded to have some of Countdown in the set. It only had two figures, a really nice looking yellow air assault, and a Hazop that seems to have been recycled from the 2011 AA gun. The last image is a prototype of the Red troop transport hog, which looked really simple and blocky on the back, which made it look sorta childish, so I’m glad they changed it.