100th is a short but deep puzzle platformer with a fairly simple difficulty curve, plus optional and difficult challenge branches (for those who feel so inclined). It is not extremely difficult to complete, but there are a lot of secrets for those hardcore completionists out there. In 100th, you play a small character with a balloon companion. There are no enemies, only environmental hazards; your fickle friend, however, makes for a uniquely challenging experience to the end.