Necrozma (Psychic type) is the final Pokemon available to capture in Pokemon Sun And Moon. To capture Necrozma, first defeat the Elite 4 and become Alola Champion. Next, complete all Ultra Beast quests for the Looker. Then, go to Ten Karat Hill on Melemele Island. Break through the boulders using the Tauros Ride HM and enter Farthest Hollow. Necrozma spawns in the grassy field in the back-left corner where Rockruffs naturally appear. There is a very low chance that Necrozma will appear, but you can do the following things to increase the chances it will appear:
-Use Super Repel to keep low-level Rockruffs from bothering you while you try to get Necrozma to spawn.
-Always keep running, or ride on Tauros and charge in circles. The faster you move, the more likely you are to enter into a random battle.
-Do not put Pokemon over Level 75 on your team. Necrozma is a Level 75 Pokemon, and will not spawn if you have Level 75+ Pokemon.
The Pokemon in Ten Karat Hill are Level 10+ at best — so Super Repel will prevent low-level Rockruffs from bothering you as you circle the grass, and only Necrozma will appear for a battle. Once it does, use the following tips to catch it:
-Necrozma is the hardest Pokemon to catch in the game. Save the Master Ball for this battle to make it much easier to catch it.
-If you do not have a Master Ball, buy a large quantity of Ultra Balls. It may require over a dozen attempts, but the Ultra Ball will eventually capture Necrozma.
-Do not use Beast Balls. Necrozma is not an Ultra Beast. Thus, Beast Balls will actually lower your chances of catching Necrozma.
-Bring Pokemon that are about Level 60+ to have a fair fight with Necrozma.
-Use Ground type special moves against Necrozma to weaken it. Necrozma is a Psychic type, and uses Iron Defense to precisely increase its defense.
-Once you have weakened Necrozma, use Yawn/Hypnosis or other moves to make it fall asleep as you attempt to catch it.