There are some glaring mistakes in this run, particularly in 3-1 (almost forgot to get the heart and some general movement errors), 3-2 (screwed up the second damage boost through the spider and the bat), and 4-2 (took an unintentional hit on the spikes and had to get a heart), but otherwise I felt that the run was pretty solid. Sub-12:20 is possible but would probably be difficult to perform. I think I'm fine with this unless somebody beats my time.