So apparently this thread has become "
Vote for the NFE!".
......Why stop now?
Rhydon @ Eviolite
Ability: whatever
EVs: 252 HP / 16 Atk / 240 SpD
Adamant Nature
- Stealth Rock
- Earthquake
- Rock Blast
- Dragon Tail / Megahorn
Plenty of experience with Pokemon that rely on Psychic + Fire coverage has made it clear that variants of those Pokemon using Psyshock as their STAB makes bulky Rock-types very troublesome foes for them to face. If this were a Xatu using Psychic I would reconsider, but
any Rhydon comfortably takes on Psyshock Xatu (unboosted Psyshock does a piss poor 11-13%, whereas boosted Psyshock does only 17-20%), provided Giga Drain isn't used; I went with standard tank Rhydon to simplify things. Rock Blast does not make contact and does at least 60% in 3 hits, putting Xatu at risk at any moment it does not go for Roost against Rhydon.
The last move is for insurance against low Rock Blast rolls, in case Xatu decides to take advantage of them with extra Calm Minds, but usually it isn't necessary since 4 hits can do upwards of 80% to Xatu while
5 hits kills it dead, so at no point would Xatu feel absolutely safe boosting against Rhydon.
You can always go SubSD Rhydon and outright render that Xatu a liability (at the cost of longevity), up to you rly