SeedAccording to
Finnisher JvB in the comments, Speak79 found the seed 3964572094364597199 which works as of Aug. 10, 2017.
How do I get a Totem of Undying?A picture of the Totem of UndyingThe Totem of Undying is dropped by a mob called the Evoker. Evokers look like grey villagers with green robes.
These mobs types are known as illagers. There are 3 and only Evokers drop a Totem of Undying. They are hostile towards the player.
By killing an Evoker, you will also unlock:
Where do Evokers spawn?The Evoker only spawns in Woodland Mansions which in turn only spawns in the roofed forest biome. Evokers only spawn with the initial spawn of the mansion and do not respawn or despawn.
How do I use the Totem of Undying?You must be holding the Totem of Undying in either hand and receive fatal damage (i.e jumping off a cliff.)