The Doctor frowned at his fellow Time Lord, he hadn’t changed at all even after all these years. He was still the same old Master “Oh Koschei…You haven’t changed one bit in all these years…I would have thought you would cast away these ideas of dominance but instead you have merely added to them obsession” He felt a deep sorrow for him, he seemed have gone further into madness and like Ten he had a desire to help him yet he couldn’t help but feel uncertain about his once friend turned enemy being in the same place. Koschei had to be in there somewhere, noting the way he behaved at first at his touch. So he decided to do something he knew he would regret if it came into fruition “then I am willing to make a trade Master…release my other self and you may stay with me… for a time…” He grinded his teeth at the thought of having the man who nearly murdered him on several occasions in his Tardis, it was a terrible thought but it wouldn’t be long hopefully or he would reject the offer entirely. It was all up to the Master which way it when.