Sly and Bentley gained the ability to crawl in Sly 2, though Bentley lost the ability after his accident. Sly kept the ability and uses it in all following games. It is used to squeeze through tight spaces, allowing escape or access to otherwise unreachable areas, often both. Crawling was first used in the mission "Breaking and Entering" in The Black Chateau (unless used prior in free-roaming), first by crawling underneath tables, and then through two air systems.