The Tenth Doctor + Taigam, Master Opportunist + Temporal Trespass
Extra Turns: Infinite turns, Lock
Cast the self-suspending card by paying its mana cost if its in your hand, or any other spell otherwise if you have not cast a spell this turn.
Cast Temporal Trespass by paying its mana cost.
Taigam triggers, copying Temporal Trespass and then exiling it with four time counters on it and giving it suspend.
Resolve the copy of Temporal Trespass, causing you to take an extra turn after this one.
Move to your next turn. At the beginning of that turn's upkeep, Temporal Trespass and the self-suspending card's suspend abilities trigger, removing a time counter from each of them.
Activate The Tenth Doctor by paying {7}, removing three time counters from Temporal Trespass and the self-suspending card, triggering their suspend abilities.
Resolve the self-suspending card's suspend trigger, causing you to cast it from exile without paying its mana cost, and eventually exile it with time counters on it.
Resolve the Temporal Trespass's suspend trigger, causing you to cast it from exile without paying its mana cost.
Repeat from step 3.
Cards: The Tenth Doctor, Taigam, Master Opportunist, Temporal Trespass