Deoxys-D

Pressure
Enemy attacks lose 1 extra PP. Increases wild encounter rate.
Type Tier
Psychic Uber
Statistics
Min- Min Max Max+
HP
50
- 241 304 -
Atk
70
158 176 239 262
Def
160
320 356 419 460
SpA
70
158 176 239 262
SpD
160
320 356 419 460
Spe
90
194 216 279 306
Name Item Nature

Spiker

Leftovers Careful
Moveset EVs
~ Spikes
~ Stealth Rock
~ Knock Off
~ Recover
252 HP / 80 Def / 176 SpD

The theory is that you'll be using this Deoxys-D on a stall team, so both types of Spikes are important. If you really want to stall, you could use it with Cloyster or Forretress to have Toxic Spikes, as well, allowing you to use moves other than Toxic.

Name Item Nature

Toxistaller

Leftovers Calm
Moveset EVs
~ Agility
~ Taunt
~ Toxic
~ Recover
252 HP / 172 Def / 56 SpD / 26 Spe

This Deoxys-D is pure evil against any team that relies on stat upping, status, or healing. After an Agility, you will be faster than even +Speed Deoxys-A. You can then Taunt anything but pure attacking moves. Looking at Deoxys-D's defenses, it can just shrug off most unboosted hits. Taunt will stop Blissey from using Aromatherapy to heal the team of Toxic, so you just have to Taunt and Recover until they die of Toxic. Beware of Metagross and Dialga.

Name Item Nature

CMer

Leftovers Bold
Moveset EVs
~ Grass Knot
~ Shadow Ball
~ Calm Mind
~ Recover / Rest
252 HP / 136 Def / 120 SpA

Deoxys-D can Calm Mind up behind that massive Defense, letting it stay protected on both ends of the spectrum. The reason Grass Knot is listed as a required move is because if you aren't using Grass Knot, you might as well use Lugia for your extremely defensive Calm Minder. You can EV a Lugia to take hits better from both ends of the spectrum, and have more Speed and Special Attack. The cost, of course, is that Lugia is weak to Thunder and Ice Beam, but it's immune to Earthquake and neutral to Bug. Since you'll be boosting your Special Defense anyway, it's physical moves you are mostly worried about. Grass Knot allows Deoxys-D to hit both Kyogre and Groudon hard, while Shadow Ball smacks around enemy Deoxys, Mewtwo, Latias, Latios and any other Psychic fiend.

Rest is to protect against status, but Recover gives you instant healing.

Ice Beam is always an option to hit Rayquaza.

Name Item Nature

Snatcher

Leftovers Careful
Moveset EVs
~ Snatch
~ Toxic
~ Knock Off
~ Recover
252 HP / 80 Def / 176 SpD

Snatch allows you to steal your opponent's Substitutes and Calm Minds, giving you a way to boost your own defensive abilities. You can Snatch as they try and Substitute, and then, when they give up with that, use Toxic on them. If they come out and try to use Aromatherapy to heal away the status, you can use that to heal your own team, instead.

Other Options

Superpower can be used if your team is having some trouble with Tyranitar or Blissey, but Deoxys-D can't take Crunches from Tyranitar, so it's more for their coming in on you and thinking they can get away with Dragon Dancing. ExtremeSpeed helps against Salac Pokémon and enemy Deoxys-A. Pursuit gives you a non-Spikes way of dealing with Shedinja, should it ever show its face, and is yet another method of Deoxys-A dismemberment. Seismic Toss and Night Shade can be used for some direct damage abilities, so you don't have to rely on Deoxys-D's piteous attacking stats. Seismic Toss has more PP, but Night Shade hits Shedinja, Gengar and Dusknoir. The Pokémon it doesn't hit, namely Blissey and Snorlax, have such massive HP that you won't be doing much to them anyway, so Night Shade is almost always superior until you run out of PP, then you'll be wishing you had a few more hits with Seismic Toss.

Counter and Mirror Coat are options, especially with Taunt and Recover, but because of Deoxys-D's high defenses, they might not do enough damage to you to KO themselves. However, they will certainly do so if they are using a super powerful attack, such as Rayquaza's Outrage or Draco Meteor. Alternately, they can be used with Agility, because that allows you to use Recover after killing something, or they may do ~80% to you, get KOed by Counter / Mirror Coat, and then send in something else to faint you. If you have used Agility, you can use Recover before they attack, and since most unboosted attacks do <50% to Deoxys-D, you will regain HP this way. With a metagame filled with Toxic Spikes, Deoxys-D can Rest / Sleep Talk to avoid being destroyed by them and also absorb incoming Dark Voids from Darkrai.

Reflect and Light Screen can prolong Deoxys-D's existence even more, or let it essentially pass on high defenses to the next Pokémon that comes out. Cosmic Power works in a similar manner, except it only helps Deoxys-D, and is removed by Whirlwind or Roar. In general, Reflect and Light Screen are superior to Cosmic Power, Amnesia and Barrier just for their pseudo-passing abilities.

EVs

First off, always max Deoxys-D's HP. Don't even think about putting a single point into any other stat before you do that. This is the single best way to extend its survivability. For most sets, you'll want to get slightly more Special Defense than Defense, just because special moves are more common.

Opinion

Deoxys-D is a great tank. However, you must take care not to make your Deoxys-D a worse Lugia. Deoxys-D's low HP means it can't take neutral hits as well as Lugia, but Deoxys-D isn't weak to Thunder, Ice Beam or Stone Edge. It has an interesting movepool, so as long as you take advantage of this, you should be fine. Deoxys-D is the single best Spiker in the game, and at the least one of the best Stealth Rockers. It learns interesting moves in Taunt, Snatch and Knock Off, and can surprise 4x weak Pokémon with something that hits them hard. In short, Deoxys-D is a monster.

Counters

In general, any Substituting Pokémon stops Deoxys-D cold. It blocks Toxic and Knock Off, two of Deoxys-D's most common forms of "offense". 101 HP Substitutes, as most high powered Pokémon can make, are also unbreakable by Deoxys-D's staple attacks, Night Shade and Seismic Toss. These Pokémon (for instance, Kyogre) can then stat up behind this Substitute and force Deoxys-D to switch to something else, giving a few free turns. Pokémon with Rest are much of the same, but at least they give a couple turns of downtime to switch out to a counter, unless it's paired with Sleep Talk.

Swellow, Ursaring and especially Heracross are also interesting choices. If they are hit by Toxic, they've suddenly gotten their Guts bonus, and potentially a Facade power doubling, as well. Heracross has the ever dangerous Megahorn, and this problem is only worsened by the possibility of Guts. Steel Pokémon in general can also prove difficult for Deoxys-D to take down, and those with any form of recovery can often last as long as their PP do. This, however, is where Deoxys-D's trait, Pressure, really shines. Unless they have Rest to waste three turns per PP, Deoxys-D is not likely to run out of PP before they do. If Deoxys-D has Knock Off, then it will at the least win in a Struggle war. Metagross is particularly troubling, because of the potential for a Meteor Mash Attack up. In a similar manner, Dialga can use Deoxys-D as set up bait for a Bulk Up set. Scizor can set up a BP and / or attack with a Bug move. Poison Pokémon, although far rarer, also are troubling because of their Toxic immunity.

Blissey stops the Calm Mind set if it doesn't have Rest, and also laughs at Toxic thanks to Natural Cure and a potential Aromatherapy to heal the rest of the team. Celebi, too, blocks most sets.

If Deoxys-D's only goal is to lay Spikes and Stealth Rock, however, the best counter is a Rapid Spinner. Forretress is a good choice because it's immune to Toxic, but Cloyster is looking to be a decent Pokémon on the top tier. It has STAB Ice Beam to ensure it's not useless against every team without a Spiker, can Explode to severely weaken something when its job is done, and can use Rapid Spin on those Spikes and Stealth Rock that Deoxys-D tries to lay.