For 5th level or lower characters, it's a puzzle. The party must translate the ancient language of a powerful golem so they can command it and either spare their hometown or wield it as a weapon against an otherwise unstoppable threat. There's a normal version of the puzzle and a harder variant, so if your players love ciphers and language puzzles, we've got you covered!
For 11th level parties, this is a straight-up boss fight. The prime golem has a series of combat routines it can use, following them for a few rounds before switching modes. It's not the most complicated boss monster we've released, but it's more involved than a typical legendary creature.
The encounter is attached, and there's player and DM versions of the map even though the only difference is the golem's starting location. Enjoy!