The Foot Clan is a ninja clan operating in the video games based on the 2007 film in at least two locales - Japan, and New York City.
The previous leader was Shredder, an armored ninja master. Following his defeat at the hands of the Ninja Turtles, the clan remained defunct in New York until the arrival of Karai, a leader from Japan.
Karai and The Foot were hired as security detail for billionaire Max Winters. When strange monsters began appearing in New York, they were also tasked with retrieving the monsters for Winters. When they approached a Bigfoot in a construction site, the Turtles also arrived, and Karai held them off while her ninja captured the beast.
When Winters' generals captured Leonardo instead of the thirteenth monster, the other Turtles went to Winters Corp to rescue him, dealing with the Foot Clan along the way. After Winters and the generals' deaths, Karai told them that a shadow from their past may resurface. TMNT (console game) TMNT (Game Boy Advance game) TMNT (handheld game)
Some time later, Shredder returned somehow, and kidnapped Honeycutt the Fugitoid, taking him back to Japan with him, to force him to build a Transmat. After the Turtles received Honeycutt's distress call, they encountered Karai, who informed the Turtles of where the Fugitoid was being held and why. Although she didn't tell them why she was giving them this information, it was because she was vying to send Shredder packing back to wherever it was he had been so she could recover her leadership role.
The Turtles eventually rescued Fugitoid from Shredder and returned to New York. Teenage Mutant Ninja Turtles: Smash-Up (comic), Teenage Mutant Ninja Turtles: Smash-Up.