Boss 13: Iku - Touhou Souzinengi V -The Genius of Sappheiros-

game:
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playlist:
• Touhou Souzinengi V -T...
Iku on hard difficulty. Satori time! Iku has two great spells for her, I wanted Mad thunder here (hence Satori is in a dangerous position), but thunderclap aka Levin Thunder also works. Though supposedly she only uses it at 30% health...???
Oh well. Basically, as long as you have Alice with buffed resist, Reimu barrier and Sakuya skip - Iku can't ever apply her deadly combo, and it's really simple to deal with her. Sakuya with aqua slaying absolutely shreds her, but Patchouli with earth attacks also works. Iku is also very weak to dark, but Byax doesn't learn dark sword until 25.