I did not come up with this theory I got this from the youtuber Turtle Quirk.
https://www.youtube.com/channel/UChp-A9cwI6zVcDEuIXO71kQ
This theory is a theory that I think is pretty accurate. If you look at the one for all users the second and third are blocked out. The second looks like Bakugo and the 3rd looks like its Kirishima.
The hair looks the same but on his arms you can see something that looks like his grenade bracers. Bakugo probably went back in time from Eri to tell the first user he can pass down the quirk then passing it on to bakugo.
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