This is going to be really long, so if you don't want to read it, I'm basically explaining why I think your set and Deoxys-D itself isn't very good, and that the sets on Smogon's analysis are more useful in general.
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Alright before I answer I just want to set a few things straight. I don't want to sound rude, but I this set is pretty bad - this set is very passive, and is setup fodder for basically everything. Deoxys-D is a naturally passive Pokemon, yes, but what does this set do? Deoxys-D has awful offensive stats, so the attacks will do very limited amounts of damage, especially in Ubers where basically everything has decent natural bulk. Apart from attacking, it's just sitting there setting up Cosmic Power using Recover. This set would not threaten a vast majority of the Ubers game, so I highly recommend you don't use it.
The other thing I just want to say is that Defence isn't really the best Deoxys form - it's the only one that has spent time in OU rather than Ubers. It has zero offensive presence, and due to its low HP stats, it isn't too hard to break through with powerful attackers. Pure Psychic isn't a very good defensive typing either, especially in Ubers where it doesn't really give you many useful resistances and just gives you weaknesses to Yveltal, Darkrai and others. It has a niche as a hazard setter, but even then, Klefki does a better job than it does at this due to its fantastic typing and access to Prankster support moves.
With that said, we'll move on to what set you could use for Deoxys. To be completely honest, Recover is the only move on this set that is worth using on Deoxys-D. To keep it simple I'll just go over why each one isn't that great:
- Cosmic Power isn't a very good move on Deoxys, and is not a very good move in general with very few Pokemon available the prefer it over Calm Mind. Moves that raise just defensive stats are usually not worth using; the reason is that these defensive Pokemon switch out a lot when a Pokemon that beats it comes in. Switching deletes your boosts, which is the main problem with those types of moves. The other problem is that you can't exactly "sweep" a team with Cosmic Power like you can with offensively-oriented moves like Dragon Dance or Swords Dance. It's not worth using.
- As mentioned before, Deoxys has pitiful attacking stats (70 gets you nowhere), so using offensive moves is less useful, especially in Ubers which is full of Pokemon that can absorb weak attacks from Deoxys-D for ages. Psychic does get STAB, but it is still weak and isn't really doing anything for you.
- Dark Pulse is even worse. It gives you a way to hit opposing Deoxys, Mewtwo and maybe Lugia, but besides that, you will very rarely be using it. Not worth using at all. If you really feel Dark coverage is worth having, Knock Off is much better than Dark Pulse for bulky Pokemon.
Pretty much the only thing Deoxys-D does that it isn't completely outclassed at is setting hazards like Stealth Rock and Spikes, which is what you really should be using it for. Deoxys can be used as a suicide lead, who uses its bulk to stay alive long enough to set up Spikes and Stealth Rock and cripple the opponent with Thunder Wave. It can also be used as a wall that can set hazrds - as mentioned before, Spikes are the only thing Deoxys-D has over other defensive Pokemon in Ubers. Here sets for each of these roles (from Smogon since I'm lazy):
Suicide Lead
Deoxys-Defense @ Mental Herb
Ability: Pressure
EVs: 248 HP / 8 Def / 252 SpD
Calm Nature
- Stealth Rock
- Spikes
- Taunt
- Thunder Wave
Mental Herb prevents Deoxys from being hit by Taunt once, almost guaranteeing you to get one layer of hazards up unless your opponent manages to OHKO you somehow. Since this is a suicide lead, Stealth Rock is worth using over Recover. Spikes deal useful damage on switch-in and can allow Deoxys to support your attacks by weakening their targets. Taunt uses Deoxys' decent 90 Speed to stop slower Pokemon from using status moves or setting hazards of their own. Thunder Wave is more support that you can use to slow down a Pokemon and make it easier to beat with another Pokemon.
Wall/ Spike setter
Deoxys-Defense @ Leftovers
Ability: Pressure
EVs: 252 HP / 4 Def / 252 SpD
Calm Nature
- Spikes
- Recover
- Taunt / Toxic
- Knock Off / Night Shade
Does the same thing as the last one, except with moves that help you keep it alive. Recover is used for the same reason you used it in your set - it heals damage and keeps Deoxys alive. Toxic is an option over Taunt for you to start dealing some damage. The last moveslot is up to you, depending on what you want to do with this Deoxys; Knock Off removes the opponent's item and is the preferred option, but Night Shade provides more consistent damage and can 4HKO most Pokemon.
Also, Knock Off can OHKO Deoxys-A which I thought was pretty cool:
0 Atk Deoxys-D Knock Off (97.5 BP) vs. 0 HP / 0 Def Deoxys-A: 322-380 (133.6 - 157.6%) -- guaranteed OHKO
