AUSTIN (KXAN) — Superheroes and villains gave an all-out show for patients at Dell Children's Medical Center Thursday. Characters like The Flash, Wonder Woman and Ant Man rappelled down the hospital walls to battle villains like Poison Ivy, the Riddler and the Penguin. The people behind the masks were none other than Austin Police Department officers and Dell Children's associates. The Flash rappels down the side of Dell Children's Medical Center for Superhero Day. (KXAN Photo/Andy Way)The Flash rappels down the side of Dell Children's Medical Center for Superhero Day. (KXAN Photo/Andy Way)The Flash rappels down the side of Dell Children's Medical Center for Superhero Day. (KXAN Photo/Andy Way)Wonder Woman rappels down the side of Dell Children's Medical Center for Superhero Day. (KXAN Photo/Andy Way)Wonder Woman rappels down the side of Dell Children's Medical Center for Superhero Day. (KXAN Photo/Andy Way)Ant Man rappels down the side of Dell Children's Medical Center for Superhero Day. (KXAN Photo/Andy Way)Ant Man rappels down the side of Dell Children's Medical Center for Superhero Day. (KXAN Photo/Andy Way)The Riddler, the Penguin and Poison Ivy await the arrival of the superheroes at Dell Children's Medical Center for Superhero Day. (KXAN Photo/Andy Way) Children watched the whole scene unfold from their windows, and afterward, were treated to a meet-and-greet with the characters. Dell Children's said it hoped "to provide a fun-filled day for patients at the hospital," according to a news release.