100%. All negative expectancy games in a casino are 100% risk of ruin. People seem to be looking for a different answer, but I really don't know what else to tell them. Against a house with a nearly infinite bankroll and a solid mathematical edge, risk of ruin is certain. But this is due to the definition of risk of ruin. If we water the definition down some, and pretend the house has only $500 or $1000, and that we have $500 or $1000, then we have a fighting chance.