Lunala

Lunala is a mainstay defensive Pokemon often paired with the classic core of Yveltal, Eternatus, and Necrozma-DM, forming a defensive backbone that is very difficult to break. Its typing may look terrible, compounding weaknesses to Calyrex-S and Marshadow; however, it provides two immunities and a neutrality to most types. These defensive traits, Shadow Shield, Heavy-Duty Boots, and Roost let Lunala blanket check some of the most dangerous threats in the tier, such as Fire-type move Groudon, Zygarde-C, Zekrom, offensive Necrozma-DM, Rayquaza, and Mewtwo. Lunala excels in long games, where its unmatched reliability in checking strong threats gives it a unique niche. Shadow Shield also makes it a "get out of jail free" card, even stopping a Geomancy Xerneas sweep in an emergency. Lunala can also opt for a more offensive set that surprises common switch-ins like Yveltal with Meteor Beam while still offering defensive utility. However, Lunala's reliance on constantly using Roost to maintain Shadow Shield makes it one of the more predictable Pokemon in the tier. This tendency also sacrifices momentum; thus, more flexible defensive options such as Landorus-T are sometimes preferred. Lunala is also vulnerable to lure options, especially status moves such as Toxic from Groudon. Overall, the key to Lunala is using its defensive presence to let other teammates be more offensive while, at the same time, running teammates with some defensive utility of their own to make Lunala more flexible.