Place it at the exact transformation or reveal point in your edit, not during the build-up before it. Follow it immediately with the vine boom sound effect for weight, or precede a victory beat with the anime wow sound effect to underline the result.
Über diesen Sound
This is a short, strained scream from Ichigo Kurosaki as he unleashes Bankai, lasting just under five seconds with no words, just a raw yell. It feels intensely dramatic and chaotic, like determination boiling over all at once. The clip comes from Bleach, the anime and manga series where Bankai is Ichigo's powerful battle transformation.