Ryu Song in JJS seems pretty uncommon, but not impossible to run into. Based on public posts and clips, it looks like players treat Ryu’s secret awakening/variant as a rare or hidden interaction rather than a standard, frequently seen feature.

What people are seeing

  • A guide video says Ryu’s secret awakening is triggered by building the heat bar to about 3/4, then using awakening.
  • A Reddit post calls the Ryu awakening “(kinda) rare,” which suggests the odd part is the special variant/audio rather than the character itself.
  • Several recent videos and shorts are focused on Ryu combos, ultimates, and secret awakening showcase clips, which usually happens when a game element is notable or uncommon.

Practical read

  • If you mean Ryu as a character/moveset , he does not look extremely rare because there are multiple guides and combo videos about him.
  • If you mean the secret song/awakening variant , that part appears to be the rare piece people are talking about.

Quick takeaway

So the best answer is: Ryu himself is not especially rare in JJS, but the secret Ryu song/awakening variant is the rare part. That’s the pattern reflected in the public clips and discussion I found.

TL;DR: common-ish character, rare special variant.