Temporal vaccination
From Tardis Wiki, the free Doctor Who reference
Temporal vaccinations were based on the same principal as normal vaccinations, a small amount of a potentially dangerous substance building up a tolerance for the larger dosage. The Great Houses developed this technique for use in The War, bending small strands of someone's timeline into a different time period. This was used to inoculate their agents from the shock that was normally present when deployed into a new time period for missions. (PROSE: The Book of the War)
