Finally beat the Sacred Grounds in Cave Story!
Pictured: screenshot I took showcasing the time I did it in.
Completing the game in this fashion has also unlocked the extra hard optional challenges.
The Nemesis challenge was the first to be unlocked, gotten when you get the Nemesis for the first time. It's bullshit hard even for an optional challenge. I mean, it's bad enough that you have to do that entire thing with just the Nemesis, but also the fact that you only have 10 hp, the v0.8 booster, have to navigate a long series of difficult platforms above certain death the entire way, and face atleast a dozen or more enemies that spam projectiles all of which drop exp crystals. I started making good progress, and I got the V2.0 booster some ways through, but it would seem that the only way to progress after that is to get up in a tiny hole surrounded by spikes that all instakill you. I haven't gotten further than that.
I'm really liking the wind fortress though, if only because the challenge isn't tremendous like the Nemesis challenge, and it plays out like some bizarre non-canon fan fiction with an alternate floating island and an army of evil naked Curly's that all seemingly want to cannibalize you.
Boss Rush is hella fun. Nuff said.
And then there's the Sacred Grounds speedrun, at your convenience so you don't need a save file at the spot to do it. Trying it out though, it's actually much harder than an actual run through, since while the game is happy to give you 55 starting health and Booster V2.0 to start, your choice of weapons is limited. Meaning you can pick and choose any weapon you want, so long as it's not the Machine Gun, Wavy gun thing the roaches give you, or the rocket launcher. That's killer man, the rocket launcher was like the only weapon I used other than the Spur due to it's incredible DPS. It hurts so much to not be able to use it. Also, no Health Pot, now that's mean.
I guess I might try going through the game again on Curly's Story, where you play as Curly and there's alot of new dialogue for herself.