Acheron is a good sequel (yes it is one) to Tartarus in my view, it takes inspiration but is definitley it's own modern take on the gameplay style. Thermodynamix is a great song which is perfect for a sequel to Tartarus, which also used a DJ-Nate song. Acheron is by no means a level I think is good, but it us also not a level I deem to be bad either. The latter half of Acheron in particular is particularly awesome in my view, the click sync and difficult gameplay makes it a charm to watch a completion of. Acheron is evidently made out of difficulty rather than love for the game, but it is a great top 1 and Riot has dont what he sought to quite well.