To mark the long-awaited return of Batman: Arkham Knight to Steam today, Warner Bros Interactive Entertainment is showing its appreciation to patient PC players with giveaways -- including free digital copies of games from the Arkham series.

Anyone who's purchased Batman: Arkham Knight for PC prior to 11:59 p.m. PT on Nov. 16 will receive Batman: Arkham Asylum, Batman: Arkham City, Batman: Arkham Origins and Batman: Arkham Origins Blackgate in their Steam user libraries by December.

Developer Rocksteady Studios is also creating a Community Challenge Pack that will be given away in January to Batman: Arkham Knight owners. However, PC players will be given access to the maps a week before they're available for consoles.

Add to that a Steam community contest to create Batman: Arkham-inspired cosmetic items for Team Fortress 2. The winning items will be given to those who purchased Arkham Knight on Steam before the contest ends on Nov. 16.

Arkham Knight returns to Steam for months after its glitched-filled launch forced Warner Bros. to abruptly suspend sales for PC. Despite that setback, the game has already sold more than 5 million copies worldwide.