Try 'teal megrez armor' and 'megrez forehead protector (red eyes)' if the other armor tags don't work out for you.

Put 'belt' or 'leather belt' in the negative prompts if you keep getting those.

Tags for the Amethyst Sealed attack:

purple crystals, legs apart, outstretched hands, outstretched arms, transparent white crystals, green action lines, straight on, action lines, pink circles, pink energy