Speaking from 23 years of professional experience as a systems engineer/SRE, without seeing how things work on the back-end, calling for a new engine is likely mildly premature. If I were to guess, bungie doesn't have (SRE|System Eng|DevOp)s (whatever you wanna call them these days) managing infrastructure and operations. Instead, they likely have developers doing it and traditionally, that's always been a horrible idea, because frankly, they really don't have a great track record for knowing how to run operational infrastructure. Writing a whole new engine is painstaking, takes a long time, and is error prone. Besides, why throw the baby out with the bath water. It's better to fix the bugs and enhance the current engine usually. I'm curious, how have you identified that the engine needs work? From a client side of things, I have never seen any significant issues with the game play. The network suuuuucks! That could likely use some work, but as I said, we have no idea how they're running their servers as far as I'm aware. My guess is that their back-end needs some optimization. I *think* they use AWS for their back end infra (based on region names I've seen). At any rate, my guess is that this is where they need help. If they're using kubernetes, then that could cause some additional question in terms of load balancing, ingresses, etc, in my estimation. A new engine would be like taking a hammer to an ant hill I think. I doubt much good can come of that right now if your goal was to still play d2 as it currently is in form. Also, data migration is extremely difficult to perform flawlessly and almost always runs into problems. I doubt db schemas are perfect (assuming they're used, which I'm guessing they are). Migration isn't impossible, but I almost promise you it would never be done. They'd just start over from scratch minus basic player data and if you start with a new engine, that's likely what you would do...at least I would.