Disgusting Resilience

You tap into virulent necrotic magic to twist your own health and flesh into an abhorrent, fetid bulwark. As a bonus action, you may roll up to your proficiency bonus hit dice(s). Count up the amount rolled and time it by two. The amount you get is temp. hit points that lasts for the next minute. The spell fails and ends if the caster does not have one or more hit dice(s) left.