From the manufacturer:

Includes motorized Thomas train, Darcy the digger powered by Thomas, hand-cranked mineshaft feature, boulders, and a full track layout

Thomas lands on and rides upon Darcy the digger

Darcy has a rotating attachment that is powered by motorized Thomas and knocks boulders off the track

Mineshaft hand-crank can be used to bring Thomas to the top of the mine, and to send boulders cascading down

Connect to other Thomas & Friends TrackMaster train sets and expansion packs to build a bigger motorized railway (sold separately and subject to availability).