It's a Rumic World うる星やつら ザ・障害物水泳大会
Ataru and the others will join the competition of 'The Obstacle Course Swim Meet', organized by Tomobiki High Principal and Onsen-Mark. Each of Tomobiki High students need to face different kinds of obstacles during the competition, only few of them reach the finalist and their situation is getting harder and harder than previous obstacles.