Probosco

 was the caretaker of "the King".

He sneaked the Twelfth Doctor into the obstacle-ridden throne room, to get the TARDIS, guarded by a three-headed dog, back, with the Doctor's only tool being a broom. When Probosco got scared, his psychic trunk attached itself around the "bravest person in the room" — the Doctor. The two helped each other cross the obstacle course. When the trunk sensed both the Doctor and Probosco were in danger it pulled them both back up. Probosco launched the Doctor with a see-saw to get them to the TARDIS. The trunk released itself from the Doctor, and Probosco realised the Doctor may not be the bravest one in the room now. Probosco played fetch with the broom, causing the dog to chase after it. The Doctor offered to take Probosco home after he dealt with the King. (COMIC: Elephant in the Room)