While being pounced by Samarog, you lose stats from some source. Possibly your runes, sigils, and food. IF you are broken out from his pounce your stats return to normal. However, if you happen to die during the pounce, your stats will stay messed up. I was able to fix this by logging out then back in but have heard other ways as well (reequipping all your gear and food.)
Was able to reproduce easily and consistently. Simply get pounced on Samarog and check your hero panel.
Video: https://www.youtube.com/watch?v=SZOXL_-RhG0
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