It's our all time favorite mouse.
This guy was begging for an RTP, so here it goes.
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From Pichu with love, I present the angry mouse:
Pikachu
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Pokemon Name: No clue.
National Pokedex Number: #25
Metagame Tier: UU
Ability: Static (30% chance of Paralyzing opponent if Pikachu is hit with an attack that makes contact with it)
Type: Eeeeeeelectric
Base stats:
HP: 35
Attack: 55
Defense: 30
Special Attack: 50
Special Defense: 40
Speed: 90
What you'll immediately notice is that all of Pikachu's stats are way below average except for Speed, which is decent. His terrible defenses (35/30/40) won't allow him to take any kind of hit. I even doubt he will survive an Ambipom's Fake Out at full health. Of course Pikachu wouldn't be UU if he didn't have something special in the shape of Light Ball. In RSE, this item used to double Pikachu's Special Attack, actually getting a usable Sp. Atk. stat out of him. And now in DP, they decided to make Light Ball even more special by making it double Pikachu's Attack stat as well!! Isn't that great?
But aside from his Defenses, there is one major downside to this rat that prevents him from being BL or OU and that's his Speed. 90 speed is not bad, but it doesn't cut it either. Combine that with the critter's inability to hold any speed-enhancing items and it's a pain in the ***.
What I'm trying to say is that Pikachu ABSOLUTELY NEEDS his Speed maxed out, no matter what. You should prevent stuff from outspeeding you or you're dead. Be sure to have that Timid, Hasty or Naive nature combined with 31 speed IV and 252 Speed EV.
Movesets
ALL SETS ASSUME PERFECT IVS OR MODIFIED IVS TO GET HP ICE.
Pure Special Sweeper:
Pikachu @ Light Ball (Absolutely never use any other item on Pikachu)
Nature: Timid (+ Speed, - Attack)
Moves:
~Thunderbolt
~Grass Knot
~HP Ice
~Substitute
EV: 252 Sp Atk, 252 Speed, 6 Def/SpDef
Why the 6 Def/SpDef? Because you'll want to have an odd-numbered HP so you can Sub 4 times instead of 3. Without the 6 HP EV your HP will be 211, which is great because you can sub 4 times AND side damage (Spikes etc.) is rounded down. Remember this.
The key to Pikachu is to have a Sub up as much as possible. Send the critter out against something slower and predict. For example, if you send it out against Swampert, he'll probably be expecting a Grass Knot, so Sub up while he switches out. Good prediction is what makes or breaks this mouse.
Thunderbolt is your hard-hitting move that gives you a nice STAB in the back and will often deal good damage to everything that doesn't resist it.
Ground types are immune to Electricity, which is why Grass Knot and HP Ice are included, which covers a good number of threats.
Grass Knot will deal with the heavyweights such as Rhyperior and Swampert (Pikachu with 252 SpAtk will easily OHKO (115% min.) max HP/DEF Impish Swampert) while HP Ice will allow you to beat Dragons like Garchomp and Salamence. Keep in mind that you have to know whether the Dragon will outspeed you or not when you haven't got that Sub up. You will outspeed Adamant and Modest versions of Mence and Chomp but fail against the Timid and Jolly ones.
Blissey walls this set with the greatest ease, so watch out.
P.S. There's no Surf on this set for reasons you probably already know (Hardy PBR Pikas) and no Nasty Plot because that's countered too easily.
However:
Mixed Sweeper
Pikachu @ Light Ball
Nature: Naive/Hasty (+ Speed, - SpDef/Def)
Moves:
~Thunderbolt/Volt Tackle
~Brick Break/Focus Punch
~Grass Knot/HP Ice
~Substitute
EV: 152 Attack, 100 SpAtk, 252 Speed is your best bet.
Now Light Ball also doubles Pikachu's attack, you can abuse it's attack stat as well :o And that's great news, because now Blissey and Tyranitar (in Sandstorm he will not take too much damage from your Grass Knot) are not going to wall your *** anymore.
I did some calcs and found out that you need 244 Atk EVs to get a sure 2HKO on standard Blissey (148 HP, 252 Def, Bold) with Brick Break. That's why I suggested Focus Punch too, which is more rewarding if you get them on the switch or from behind your sub.
Thunderbolt is still for hard hitting and STAB, although you might want to consider Volt Tackle, as it is a beast. I calculated it can easily 2HKO Bliss but don't even think about that, as the recoil will have you done for soon. Outside of that, it hits a lot of stuff hard and is a nice surprise if your opponent is expecting a Thunderbolt. It even puts a huge dent in Skarmory (kind of expected). Just don't go crazy with it, or the recoil can wear you down pretty soon.
Grass Knot and HP Ice are again for coverage as you'll want to shrug off some of those big mean guys.
Last, but not least:
Encore Subber
Pikachu @ Light Ball
Nature: Timid
Moves:
~Thunderbolt
~Grass Knot/HP Ice
~Substitute
~Encore
EV: 252 SpAtk, 252 Speed, 6 Def/SpDef
The EVs are obvious I think. It's simple but requires great prediction. If you can predict a slower opponent's stat up move that is not Agility, you get a free sub. Use Encore with caution. Otherwise, just seek for other ways to get up the Sub and get a nice sweep.
The Physical Sweeper
Pikachu @ Light Ball
Nature: Jolly/Hasty/Naive
Moves:
~Volt Tackle/ Thunderpunch
~Focus Punch
~Substitute
~Encore
EV: 252 Attack, 252 Speed, 4 Defense/Sp.Def
The purely Physical side of Pikachu. A nice surprise as people will often expect a Special Pikachu. Volt Tackle will hurt stuff badly at the cost of your not-so-awesome HP. It will, I say it once again, hurt him badly. Focus Punch owns Blissey hardcore with a OHKO. Substitute is the obvious choice for reasons I've already stated, but this time it also guarantees a Focus Punch. Encore stuff to get the Sub up. You MIGHT want to replace Encore with Grass Knot or HP Ice, as it will give you lots more coverage. With a Hasty or Naive nature Pikachu's Special attack isn't too bad (it still gets doubled), so both moves are usable.
Counters
Blissey obviously has a good time dealing with the Special attackers, but dislikes the Mixed Sweeper and the Physical Focus Puncher. Dugtrio can trap revenge kill you with a 100% success rate. Stong Pokemon with a priority attack like Ice Shard or Quick Attack will beat Pikachu. Any basically, when Pikachu is not behind a sub, everything faster than it with a random attacking move is a counter. It's that fragile.
Summary
Stuff in random order:
1) Pikachu is a Glass Cannon like Rampardos. Hits hard, can't take a hit. In fact, Pikachu by far takes hits worse than Rampardos.
2) Could anybody give me some Pika info when it comes to the UU metagame? I'm not really familiar with it.
3) No Nasty Plot. Don't even think about it.
4) No Surf either.
5) Sub owns too much.
6) Encoring a stat-up move feels good.
7) It's ability Static can be useful. Kind of a 'Haha, I screwed you back' when your opponent just Fake Out KO'd you.
8) Volt Tackle is a monster, but hurts.
Movepool: other options
Besides all the options you've seen above there's some note worthy stuff left.
Physical:
Quick Attack and Fake out, because they counter those stupid Reversal sweepers.
Thunderpunch, if you dislike Recoil that much. It's still inferior to Volt Tackle though.
Present, because who doesn't love to get a gift in the form of a bomb (or an apple if you're lucky)?
Special:
Thunder, if you're a power freak and don't care about Accuracy too much.
Discharge, if you prefer the higher Para chance over a little more power from Thunderbolt.
Support
Thunder Wave, instead of Encore if you're feeling lucky. Cripple an incoming faster opponent and either attack if you're feeling like you can OHKO him or Sub and hope the opponent gets fully paralyzed before you die.
Light Screen, if you're desperate to have an extra wall of glass up. It's not a good idea.
Agility on the switch. O_o Why haven't I though of that before. Any opinions on this?
Wish, not.
That's it, my first RTP ever. Enjoy, folks.
This guy was begging for an RTP, so here it goes.

From Pichu with love, I present the angry mouse:
Pikachu

Pokemon Name: No clue.
National Pokedex Number: #25
Metagame Tier: UU
Ability: Static (30% chance of Paralyzing opponent if Pikachu is hit with an attack that makes contact with it)
Type: Eeeeeeelectric
Base stats:
HP: 35
Attack: 55
Defense: 30
Special Attack: 50
Special Defense: 40
Speed: 90
What you'll immediately notice is that all of Pikachu's stats are way below average except for Speed, which is decent. His terrible defenses (35/30/40) won't allow him to take any kind of hit. I even doubt he will survive an Ambipom's Fake Out at full health. Of course Pikachu wouldn't be UU if he didn't have something special in the shape of Light Ball. In RSE, this item used to double Pikachu's Special Attack, actually getting a usable Sp. Atk. stat out of him. And now in DP, they decided to make Light Ball even more special by making it double Pikachu's Attack stat as well!! Isn't that great?
But aside from his Defenses, there is one major downside to this rat that prevents him from being BL or OU and that's his Speed. 90 speed is not bad, but it doesn't cut it either. Combine that with the critter's inability to hold any speed-enhancing items and it's a pain in the ***.
What I'm trying to say is that Pikachu ABSOLUTELY NEEDS his Speed maxed out, no matter what. You should prevent stuff from outspeeding you or you're dead. Be sure to have that Timid, Hasty or Naive nature combined with 31 speed IV and 252 Speed EV.
Movesets
ALL SETS ASSUME PERFECT IVS OR MODIFIED IVS TO GET HP ICE.
Pure Special Sweeper:
Pikachu @ Light Ball (Absolutely never use any other item on Pikachu)
Nature: Timid (+ Speed, - Attack)
Moves:
~Thunderbolt
~Grass Knot
~HP Ice
~Substitute
EV: 252 Sp Atk, 252 Speed, 6 Def/SpDef
Why the 6 Def/SpDef? Because you'll want to have an odd-numbered HP so you can Sub 4 times instead of 3. Without the 6 HP EV your HP will be 211, which is great because you can sub 4 times AND side damage (Spikes etc.) is rounded down. Remember this.
The key to Pikachu is to have a Sub up as much as possible. Send the critter out against something slower and predict. For example, if you send it out against Swampert, he'll probably be expecting a Grass Knot, so Sub up while he switches out. Good prediction is what makes or breaks this mouse.
Thunderbolt is your hard-hitting move that gives you a nice STAB in the back and will often deal good damage to everything that doesn't resist it.
Ground types are immune to Electricity, which is why Grass Knot and HP Ice are included, which covers a good number of threats.
Grass Knot will deal with the heavyweights such as Rhyperior and Swampert (Pikachu with 252 SpAtk will easily OHKO (115% min.) max HP/DEF Impish Swampert) while HP Ice will allow you to beat Dragons like Garchomp and Salamence. Keep in mind that you have to know whether the Dragon will outspeed you or not when you haven't got that Sub up. You will outspeed Adamant and Modest versions of Mence and Chomp but fail against the Timid and Jolly ones.
Blissey walls this set with the greatest ease, so watch out.
P.S. There's no Surf on this set for reasons you probably already know (Hardy PBR Pikas) and no Nasty Plot because that's countered too easily.
However:
Mixed Sweeper
Pikachu @ Light Ball
Nature: Naive/Hasty (+ Speed, - SpDef/Def)
Moves:
~Thunderbolt/Volt Tackle
~Brick Break/Focus Punch
~Grass Knot/HP Ice
~Substitute
EV: 152 Attack, 100 SpAtk, 252 Speed is your best bet.
Now Light Ball also doubles Pikachu's attack, you can abuse it's attack stat as well :o And that's great news, because now Blissey and Tyranitar (in Sandstorm he will not take too much damage from your Grass Knot) are not going to wall your *** anymore.
I did some calcs and found out that you need 244 Atk EVs to get a sure 2HKO on standard Blissey (148 HP, 252 Def, Bold) with Brick Break. That's why I suggested Focus Punch too, which is more rewarding if you get them on the switch or from behind your sub.
Thunderbolt is still for hard hitting and STAB, although you might want to consider Volt Tackle, as it is a beast. I calculated it can easily 2HKO Bliss but don't even think about that, as the recoil will have you done for soon. Outside of that, it hits a lot of stuff hard and is a nice surprise if your opponent is expecting a Thunderbolt. It even puts a huge dent in Skarmory (kind of expected). Just don't go crazy with it, or the recoil can wear you down pretty soon.
Grass Knot and HP Ice are again for coverage as you'll want to shrug off some of those big mean guys.
Last, but not least:
Encore Subber
Pikachu @ Light Ball
Nature: Timid
Moves:
~Thunderbolt
~Grass Knot/HP Ice
~Substitute
~Encore
EV: 252 SpAtk, 252 Speed, 6 Def/SpDef
The EVs are obvious I think. It's simple but requires great prediction. If you can predict a slower opponent's stat up move that is not Agility, you get a free sub. Use Encore with caution. Otherwise, just seek for other ways to get up the Sub and get a nice sweep.
The Physical Sweeper
Pikachu @ Light Ball
Nature: Jolly/Hasty/Naive
Moves:
~Volt Tackle/ Thunderpunch
~Focus Punch
~Substitute
~Encore
EV: 252 Attack, 252 Speed, 4 Defense/Sp.Def
The purely Physical side of Pikachu. A nice surprise as people will often expect a Special Pikachu. Volt Tackle will hurt stuff badly at the cost of your not-so-awesome HP. It will, I say it once again, hurt him badly. Focus Punch owns Blissey hardcore with a OHKO. Substitute is the obvious choice for reasons I've already stated, but this time it also guarantees a Focus Punch. Encore stuff to get the Sub up. You MIGHT want to replace Encore with Grass Knot or HP Ice, as it will give you lots more coverage. With a Hasty or Naive nature Pikachu's Special attack isn't too bad (it still gets doubled), so both moves are usable.
Counters
Blissey obviously has a good time dealing with the Special attackers, but dislikes the Mixed Sweeper and the Physical Focus Puncher. Dugtrio can trap revenge kill you with a 100% success rate. Stong Pokemon with a priority attack like Ice Shard or Quick Attack will beat Pikachu. Any basically, when Pikachu is not behind a sub, everything faster than it with a random attacking move is a counter. It's that fragile.
Summary
Stuff in random order:
1) Pikachu is a Glass Cannon like Rampardos. Hits hard, can't take a hit. In fact, Pikachu by far takes hits worse than Rampardos.
2) Could anybody give me some Pika info when it comes to the UU metagame? I'm not really familiar with it.
3) No Nasty Plot. Don't even think about it.
4) No Surf either.
5) Sub owns too much.
6) Encoring a stat-up move feels good.
7) It's ability Static can be useful. Kind of a 'Haha, I screwed you back' when your opponent just Fake Out KO'd you.
8) Volt Tackle is a monster, but hurts.
Movepool: other options
Besides all the options you've seen above there's some note worthy stuff left.
Physical:
Quick Attack and Fake out, because they counter those stupid Reversal sweepers.
Thunderpunch, if you dislike Recoil that much. It's still inferior to Volt Tackle though.
Present, because who doesn't love to get a gift in the form of a bomb (or an apple if you're lucky)?
Special:
Thunder, if you're a power freak and don't care about Accuracy too much.
Discharge, if you prefer the higher Para chance over a little more power from Thunderbolt.
Support
Thunder Wave, instead of Encore if you're feeling lucky. Cripple an incoming faster opponent and either attack if you're feeling like you can OHKO him or Sub and hope the opponent gets fully paralyzed before you die.
Light Screen, if you're desperate to have an extra wall of glass up. It's not a good idea.
Agility on the switch. O_o Why haven't I though of that before. Any opinions on this?
Wish, not.
That's it, my first RTP ever. Enjoy, folks.