anueutsuho said:So, we now know what exactly causes this glitch to occur:
“It’s a stack overflow. ZUN never imagined stacks of heights larger than 15 would happen, so he capped it there. (Slot 16 acts as a failsafe) Merlin, however, calls enough functions to go over the limit. If you time out on all of her patterns from the 2nd non onwards, it can prevent a function that spawns particles from completing, each time, so it remains on the call stack. This causes her to, on the final spell, return to the 3rd spell function instead. (The final spell function goes beyond the stack height limit). Basically, you can time your kills on 2nd non, 1st spell, 3rd non and 2nd spell a certain way, such that Merlin’s behaviour on the final spell will be messed up. It’s not random; it’s actually humanly executable!
The only reason this glitch was so extremely rare the whole time.. was that the conditions were so specific, that without knowing the timings, meeting them all was essentially a very small random chance. Plus, you have to face Merlin, which almost no one does.”
As to how you face Merlin every time:
“Whose first two nonspells you get depends on who you are using. Sakuya gets Merlin, meaning Sakuya is required for this glitch to occur. Whose third nonspell and second spell you face depends on who receives the most damage during the first spell. You can just pick Merlin here.”
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