Where is my "Rampage" coming from?

Sorry for that stupid question, but this irks me since a few months actually. I played a FROSS COC build and for whatever reason have rampage, but for the love of me I cannot find out where its coming from.

This is my character

https://poe.ninja/poe1/builds/keepers/character/ComMcNeil-6761/IP_FROSSCOC?timemachine=week-5&i=0&search=timemachine%3Dweek-5%26name%3Dip_frosscoc

anyone got any idea? Thanks...