It's also a lot more complicated than it sounds. I am going to explain. To evolve Tutafeh into the new Tutétékri form, you must take 49 damage with a single hit. It is not easy, especially if you want to increase the level of Tutafeh to a reasonable level. I leveled Tutafeh around Lvl. 30, and there is a way to make it easier.
How to evolve Tutafeh into Tutétékri | Rare evolution guide
Before you can transform Tutafeh into Tutétékri, you must find a Tutafeh. I found Tutafeh as part of a Max Raid battle, but you can also find the Galask Tutafeh on Route 6. You can also exchange an Unovan Tutafeh at Ballonlea - but you won't be able to modify it with this method.
Once you have Tutafeh, to evolve it you must take 49 damage. 49+ HP of your maximum HP is all you need. It's weird, but that's how it works. Do not heal!
Take Tutafeh (with 49 or more HP removed) to the Dusty Bowl in the Wilds. The difficulty is that Tutafeh must take more than 49 damage in a single hit. Make sure to bring a high level Tutafeh!
- NOTE: The easiest way to take up to 49+ damage in a single hit is to fight a high level enemy in the Wilderness with Tutafeh - equip Tutafeh with the Focus Keeping Item. This item allows any Pokémon holding it to survive a fatal attack with 1 HP. Find a Concentrated Belt in Hammerlocke.
Save your game if you take more than 49 damage in a single attack, then head to the Dusty Bowl. Find the massive stone structure - it's the giant flat stone resembling Stonehenge. When you walk below with Tutafeh in your party, Tutafeh will immediately evolve. Make sure you walk all the way to the arch!
Tutétékri is a huge spooky stone possessed by a ghost. He is an Earth / Ghost type with high defense, special defense, and HP. It's an extremely rare Pokémon and one of the strangest evolutionary methods in the series. It's a fun challenge trying to add this type to your Pokedex.