It’s hightower…what more do you want us to say?
Go forth, son, and spread stalemates.
Keep an eye on the in-game clock, and make sure to always stick a mini-sentry in the shed facing Merasmus’ house during the Witching Hour, because then it’ll shoot all bridge-crossing enemies to clumsy, painful deaths.
When that’s not happening, plant your sentry on that incline, where the other three engineers have their sentries. Wrangler can completely shut down both directions, or just a non-wrangled sentry if you have a short attention span. I’ve seen two engineers hiding behind crates whacking the same level 3 sentry as it tanks two Monoculi. And they weren’t even using the Wrangler.
Invisible demomen are your main concern, but a single pyro dedicating his life to protecting your gear solves that.
Shuffling off the mortal coil will be the best thing that ever happened to you.
I’m not sure why they call it Hell, really it’s more like a heaven. Your mini-sentry can see the entire central area from your spawning rocks, and almost everyone needs to run down a long, narrow lava-encircled path that is practically begging you to peck people off the sides with Wrangler.
The only possible downside I can think of to playing Engineer on Helltower is that nagging little feeling at the back of your spine that you’re just doing this to ruin everyone’s fun. But those can easily be ignored!