I know he is a cute grill and not a cute girl, but Charles Babbage is really a stellar Servant with all his upgrades available. In isolation, a 40% Attack Up for 3 turns and an Invincibility for 1 turn on a 5-turn cooldown is kind of absurd.
Anyway, we had some writeups lying around that we really need to port to the site. They concern some of the older Servants that do need an update. That said, with his banner live, this one is actually current too.
We have a Fionn, Boudica and Edison rewrites in the bank, so you have those to look forward to. Very popular, I know!