I feel like I’ve made the levels too hard, but I mean…I can’t even 1-ALL any of those “old-school” shmups (like dodonpachi or striker 1945), so I guess yes someone will be able to make it to the end of the game(´•ω•`)
Closest I've ever got to a Cave 1cc is Futari, where I can get to the final boss but not kill it. Lousy at DDP, a little better at DOJ, but Mushi is where my heart lies (hence the purple bullets in my jam entry!)