Weaknesses: Fighting (2x)
Resistances: None
Immunities: Ghost

Strategy:

Nasty Plot makes Porygon-Z an extremely dangerous Pokemon. In one turn, it's Special Attack can go from an already high 405 to an astounding 810, and Life Orb will boost it even higher.

With the boost from Adaptability factored in, Tri-Attack has an amazing 160 power. That coming from Porygon-Z's massive Special Attack will hurt anything that doesn't resist Normal moves. The chance of inflicting Burn, Paralysis, or Freeze on the opponent make this move even more appealing.

The other two moves on this set are there to cover the three types that resist Normal - Ghost, Rock, and Steel. Dark Pulse makes short work of Ghost types that try to wall Porygon-Z while Hidden Power Fighting is its best option against Rocks and Steels. Ice Beam is a alternative in the event you are unable to obtain the right Hidden Power. It has good coverage against Ground, Dragon, Grass, and Flying opponents.

You'll want to have either a Modest or Timid Nature for this set. Modest gives you a rather large Special Attack boost, but it leaves your Speed something to be desired.  Meanwhile the speed boost from a Timid nature will allow you to outrun Salamence, Adamant Garchomp, and other threatening Pokemon.

Other options: Hyper Beam (TM15), Return (TM27), Hidden Power Ground (TM10), Hidden Power Fire (TM10), Shadow Ball (TM30), Agility (Level 15)

Hyper Beam is normally discouraged on any Pokemon, but gets special mention for Porygon-Z. With Adaptability, a Life Orb, Nasty Plot, and a Modest Nature, Hyper Beam becomes a sure OHKO on the standard Blissey. This is pretty impressive considering that Blissey is the best special wall in the game.

If you want a different way to hit Blissey that doesn't involve losing a turn after you attack, you can use Return. Porygon-Z's Attack is average, but Adaptability will give Return over 200 power and Life Orb will boost it even higher. Plus it's physical so it targets Blissey's low Defense and can take her out in two hits.

Hidden Power Ground is similar to Fighting, but it's more effective against Heatran and can also handle Metagross. Porygon-Z can't learn Flamethrower or Fire Blast, so Hidden Power Fire is its best Fire attack. You can hit Metagross, Jirachi, Bronzong, and other Steel types hard, but you'll be helpless against Tyranitar and Heatran.

Shadow Ball has the same power as Dark Pulse and has a small chance of lowering the opponent's Special Defense. Agility will boost its Speed even higher than Choice Scarf can. Don't use Agility and Nasty Plot on the same set though. You'll limit your attacks too much and you won't have time to setup anyways.

How to counter Porygon-Z:

Despite its ability to Nasty Plot, Porygon-Z still has trouble against Blissey. The pink egg can easily paralyze it with Thunder Wave and ruin its chances of a sweep. A Blissey with a Calm nature can also stand up to more special hits.

Spiritomb is immune to both Tri-Attack and Hidden Power Fighting and isn't weak to any of its other attacks. It has good Special Defense, can stop Nasty Plot with Taunt, and hit it with Sucker Punch when it tries to attack.

If Porygon-Z doesn't have Hidden Power Fighting, many Steel types can counter it as long as they aren't weak to Ice or Electric. Bronzong, Jirachi, Metagross, Heatran and Registeel can all do a great job of walling its attacks. Lucario can easily OHKO it with Close Combat or Aura Sphere, but is less durable and will have trouble if it switches in on a Thunderbolt. Tyranitar gets a mention because it resists Normal and Dark and will gain a Special Defense boost from its Sandstorm to better handle Porygon-Z's other attacks.

The Choice sweeper is easier to counter than the Nasty Plot sweeper since Porygon-Z will be more restricted and can't boost its Special Attack to incredible heights.

Links to Pokedex Entries

Bulbapedia
LegendaryPokemon
Psypoke
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