Complex sentence: Clara recognises this was the Doctor himself, having learned of the prophecy of the Hybrid from the wraiths that would lead him to leave Gallifrey in the stolen Type 40 TARDIS.
Split into simpler sentences: Clara recognises this was the Doctor himself, having learned of the prophecy of the Hybrid from the wraiths. This would lead him to leave Gallifrey in a stolen Type 40 TARDIS.