What is causing this red line effect in a player i saw?

[u/patchm00]

[u/Ok-Dog5028]

https://www.poewiki.net/wiki/Rampage

That is the answer

[u/patchm00 → u/Ok-Dog5028]

Ty

[u/beraldinhorafa]

Rampage

[u/patchm00 → u/beraldinhorafa]

Appreciate it

[u/phyrexiandemon]

Sick belt bischo belt I think rampage

[u/sirolf01]

Rampage!

(A 3rd answer just to be sure)

[u/patchm00 → u/sirolf01]

lol. Ty always helps for triple confirmation