Oh Dear
Not the sort of think I record actually!
But I'd guess on my worst ever day, something like about $300-400...
That's SERIOUS for you KK
I played Thunderstruck in the Casino Action tournament, and let it run on autoplay set to catch wins of 750x line (5 Hammers has a 200 extra prize). It didn't stop for ages, and I didn't hear the galloping free spins. Although I was betting at a miserly 0.27p per spin, I found my balance down 200 in around an hour. I was shocked that the negative spell had gone on for several thousand spins without respite, and stopped the slot.
My worst day ever was blowing everything I had won the previous day chasing "the streak". I had, instead, an exceptional spell in the opposite sense to the earlier session at the other casino. I did at least make VIP after only 2 months of membership, and am pretty even at the group as a whole, probably going ahead recently. The damage was thousands, rather than hundreds, and I was annoyed that I had gone "on tilt" rather than taking a more sensible view by playing at a different casino.
Now, if one casino just seems permanently bad, I deposit at another one instead of continuing to chase the upturn. I seem to do better this way, as I often hit a nice run at some stage and losses overall are much smaller, and sometimes I hit a real winning streak.