Complex sentence: Their plan had been to do another first-person shooter as their next game, however, the initial screenshots of id Software's "Quake" had just been released, and Jones felt Bungie's new game would be too similar.
Split into simpler sentences: Their plan had been to do another first-person shooter as their next game. However, the initial screenshots of id Software's "Quake" had just been released, and Jones felt Bungie's new game would be too similar.