1) Flare Blitz
Flareon: This should be very obvious. When Fire Fang is you're strongest STAB move, you know something's wrong. Flareon will still suck even with Flare Blitz, but it deserves this move more than any other Pokemon deserves any other move (Just about every aspect of this Pokemon points to it being able to learn Flare Blitz, e.g. pure Fire Type, high attack, the move is even part of it's name, ect.), and it will continue to be a complete joke until it gets it.
Entei: Same reasons as above. This should be a natural level-up move.
Camerupt: Same as Entei really, except Camerupt is worse and slower, but it could be a much better physical Trick Room Sweeper now. Obviously, with Volcanoes on it's back, this fits Camerupt very well.
Garchomp: Yes, Garchomp is already ridiculously powerful enough but he would appreciate a better fire move than Fire Fang so he can finally Blast through Skarmory and Bronzong easily and won't need to sacrifice ev's to go mixed with Fire Blast. It also just kind of makes sense to me, design wise. Flare Blitz implies a high speed rampaging charge attack, and Garchomp is the "Mach" Pokemon. The Red and Yellow color designs along with the gold star on it's head also contribute to this.
Groudon: Fits flavor wise as Groudon gets psuedo STAB thanks to it's ability and could be useful for more offensive sets such as Rock Polish to blast through Pokemon such as Skarmory and Grass Arceus.
Wargle: Flare Blitz finally give Wargle a reason to abuse it's encourage ability, which not only pumps up the power of FB considerably, but also removes Life Orb recoil. I initially hadn't even considered Wargle at all for Flare Blitz but reconsidered when I realized it fits rather well too (much better than any other Normal/Flying at least). Wargle is a Warlike Bird of Prey with Red Coloration and this move fits both these attributes.
Moltres: Flavor mainly, it fits perfectly but I doubt it would ever use it.
Ho-Oh: Same as above, though it might see some use with more purely offensive players.
2) Recover/Softboiled/Slack Off/Roost
Snorlax: Another obvious choice, due to it's exceedingly lazy nature (even it's name) Slack Off fits Snorlax perfectly and it deserves this move almost as much as Flareon deserves it's move. Snorlax has wanted this move for generations. Relying on Rest/Sleep Talk isn't good enough, especially when Snorlax needs all the coverage moves he can get and is immune to Poison anyway (with Immunity). With Slack Off, Snorlax will be relevant again.
Regice/Regirock/Registeel (Recover): All three of these trio-Legends are highly defensively-oriented Pokemon with no reliable recovery move. Regice will become a much better Hail Staller (with Ice Body), Curser, and Special Wall, Regirock will be able to carry both Earthquake and Stone Edge/Rock Slide for Curse sets, which will be monstrous in Sandstorm, and Registeel will become an even better lower tier wall. It fits design wise as well. Being elemental golems, the Regi's could accumulate more of their respective element to recover energy. E.G. Regice gathers water from the air, freezing it and restoring it's power/body mass, Regirock attatches more Rocks to itself, and Registeel restores energy internally, being (apparently) some sort of mechanized being.
Exeggcutor (Softboiled): Fits flavor wise, seeing as it's pre-evolutions are a group of eggs. Not all that useful competitively however.
Ho-Oh/Lugia: Should learn Roost by Level-up. I know they have Recover, but Roost helps remove weaknesses and they both lose it if they want to use their excellent Dream World Abilities.
Wargle (Roost): Fits flavor wise obviously, and it's counterpart Barujina even gets it! This would help to further distinguish Wargle from Staraptor (who mostly outclasses it) thanks to it's superior bulk.
Hypno/Gardevoir/Gallade (Recover): All are relatively bulky Psychic Types (on the special side), especially Hypno, who could make use of an instant recovery move. All three already have Wish, admittedly, but Recovery could be useful for Hypno and Gardevoir's defensive sets, and could be useful on a Bulk-Up set for Gallade. It fits very well on them design wise, being Psychic Types.
Tentacruel (Recover): Tenta is already a great bulky water with several unique qualities, and could definitely use an instant recovery move so it can repeatedly come in to set up Toxic Spikes and Rapid Spin. Many Pokemon with Recover have amorphous bodies, such as fellow Bulky Water Type Jellyfish Burungeru, so it makes sense for Tentacruel to get it as well.
Drifblim (Recover): Driflblim is underused defensively, despite it's mammoth Hp stat. Part of this is due to it's horrible defenses, and part of it due to having no reliable recovery move. While Roost would be more useful for Drifblim in order to shed it's flying weaknesses, Recover makes more sense. Being a Balloon/Blimp, it could fill itself with hot air again to gain energy and body mass.
Weezing (Slack Off): Weezing has always been a great defensive Pokemon, with it's high defense and having only rather rare weakness. It shuts down tons of Pokemon in the lower tiers but lacks a reliable recovery move to keep itself healthy throughout the match. Slack Off would be a great improvement for Weezing, and it fits pretty well flavor wise as Weezing is a rather indolent seeming Pokemon anyway.
3) Sucker Punch
Weavile: First of all, it fits Weavile extremely well, due to it's deceitful nature. Second, it would appreciate a better Dark STAB than Night Slash, and despite it's excellent speed, more Priority could be useful for SD Weavile when facing Scarfers, or even Mewtwo.
Tyranitar: As said in previous posts, Tyranitar would very much like to have some strong STAB priority. It could use this to great effect with Pursuit to play mind-games with Pokemon similar to Collosoil in the CAP Metagame. For example, Pokemon that think they will be dead anyway if they switch out will just attack T-tar to at least dent it and get immediately killed off by Sucker Punch. Also useful for Sub-Punch ("BOAH") sets. And, of course, it fits Tyranitar, being a Dark Type.
Zuruzukin: Sucker Punch fits this thing so well it could be it's signature move. First off, Sucker Punch has elements of both Dark Types and Fighting types--which are the types that make up Zuruzukin. Second, this thing is apparently based off of Yakuza/Gangsters, which use dirty tactics to fight (e.g. sucker punches). Third, a priority move is very useful for such a slow attacker as Zuruzukin, especially on Bulk Up Sets.
Crawdaunt/Drapion: Both are Dark Type Arthropods with dangerous claw-like limbs that could be used for a sudden attack. Both are also physically offensive, and could use a priority move due to mediocre or slow speed.
4) Trickery
Umbreon: It fits it, being a Dark Type, and would allow it to bypass it's low attack
Spiritomb: Fits it very well, seeing as it's an amalgamation of malevolent spirits. Might see use on Max/Max defensive sets due to the lack of offense.
Gengar: Purely for flavor, but a very fitting flavor it is.
5) Tail Glow
Ampharos: Another Obvious choice. First off, Ampharos has A GLOWING TAIL. Hmm... Also, it has great Sp.atk and could use a good boosting move.
Charizard: See above. Charizard's good special attack is often overlooked as it has so many ways to boost it's inferior physical attack. With Tail Glow it could be a respectable sweeper in the lower tiers. Also, with it's dream world ability Solar Power, and Tail glow, Charizard will be near impossible to wall in the sun. In one turn it gets +4 Special attack and a Sun-Boosted Fire Blast that Max/Max Calm Blissey doesn't even have a shadow of a chance at surviving. Even 4x resistors such as Kingdra are OHKO'd.
Lanturn: Same argument as Ampharos, except that it exchanges good special attack for actually being a good Pokemon. (and it's "bulb" glows, not it's tail)
Luxray: Flavor really. It's not sweeping anything - even in the low tiers, with that horrible speed.
Raikou: Calm Mind is kind of useless on Raikou compared to Tail Glow. It needs a power boost, not a Sp.def boost, since the most common attack coming at it will be Earthquake. Tail Glow will allow Raikou to become a very respectable sweeper with it's excellent 115 base Speed.
6) Aura Sphere
Alakazam: A powerful special attacker that has to rely on the unreliable Focus Blast for coverage. Also, it fits, being a mystical Psychic Type.
Gardevoir/Gallade/Medicham: Mostly for flavor, though it could be useful on Gardevoir. Both Psychic and Fighting Types have associations with this move.
Meloetta: Same as Gardevoir really.
7) Wood Hammer
Tropius: It could certainly use a move with higher base power with it's poor attack stat, and the recoil would be offset by being able to Roost or abuse Lum Rest with Harvest. Both SD and DD sets would greatly appreciate this move, and Tropius is about the only Pokemon that would make sense with this move that doesn't already have it. It is based partly on Tropical Trees after all.
Apart from Tropius however, I'm not even sure why this move is here. No Pokemon desperately needs it, it doesn't really fit any Pokemon other than the ones who already learn it (aside from Tropius), and nothing would use it but Grass Types anyway, who usually have better STAB moves to be using (usually Special moves too).
8) Nasty Plot
Mewtwo: Same deal as Raikou. Nasty Plot gives Mewtwo immediate power, and could allow him to easily sweep teams once scarfers have been eliminated. It fits perfectly as well, since Mewtwo is a tortured soul created by Genetic manipulation and has high intelligence.
Gengar: This fits so well it may as well be Gengar's signature move. The only reason he doesn't currently have it must be because it would seemingly make him broken. I'm not convinced however. With Nasty Plot, Gengar would essentially be a Darkrai with better typing, but worse stats and an inferior sleep move. We don't even know if Darkrai is broken in Gen V yet, and considering Gengar is (arguably) less dangerous than Darkrai, this won't necessarily make him broken. Just very, very good.
Sazandra: This Psuedo Legendary has a distinct lack of boosting moves (Cheer Up sucks, badly). Nasty Plot allows it to take advantage of it's excellent Special Attack (unique among Psuedo's) and great coverage. It is also classified as the Brutality Pokemon and is a Dark/Dragon type. I'd say this move fits it.
Giratina/Giratina-O: Giratina is another Dragon with a lack of boosting moves. Although it's special movepool isn't all that great it might be able to make decent use of this move, and more importantly it fits it very well, being a Ghostly Dragon with the power to rip holes in the fabric of reality.
Banette: A Ghost with a Grudge. Has mediocre Special Attack, but it fits very well.
Shandera: Similar to Banette, except for the Special Attack. Shandera, of course, has monstrous Special Attack, but is still to slow and frail to sweep with it. It fits the Ghostly Chanderlier quite well however.
Furijio: Look at it's face. Does it not look like it's plotting something nasty deep within it's icy void of a mind? Furijio also has good Special Attack, Great Speed, and nice offensive typing so it would be a respectable user of Nasty Plot.
9) Close Combat
Kirikizan: As previously stated, Brick Break is weak. Close Combat gives Kirikizan Darkrai-like coverage (but physical) combined with STAB priority, making it a good bit more threatening. It also fits very well, being (apparently) based off Kamen Rider.
Scizor/Scyther: Another Pokemon that has Brick Break for a fighting move. Scizor does get Superpower though, but Close Combat is superior. Scyther would especially appreciate this for it's SD sets. Aerial Ace+Close Combat provides the excellent Fighting/Flying coverage. Close Combat also fits well flavor-wise with both of these combative insects.
Kojondo: This Pokemon fights up close using agility, and has high attack and speed. It's fighting style seems rather similar to Infernape, who is pretty much the signature user of Close Combat. Kojondo would likely prefer to have a reliably hitting attack like this over High-Jump Kick, which can be devastating when it misses or if the opponent switches to a Ghost.
Marowak: A very fierce and brutal fighter of a Pokemon, this move fits Marowak quite well. However, due to it's STAB Earthquake, it won't be all that useful.
10) Drill Liner
Zekrom: Zekrom has a horrible movepool. It doesn't even get Earthquake. Yes, Electric/Dragon Coverage doesn't need much help, but Drill Liner is a very nice auxilliary move to take out steels reliably. It also fits quite obviously with Zekrom, considering it's Drill Engine like Tail.
Beedrill: From the very best to the very worst, every Pokemon likes to have ground moves at their disposal. Beedrill only has Brick Break to hit Steels with, and Drill Liner has more power and also comes with a high Critical-hit ratio, which is very nice for Dream World Beedrill's Sniper ability. It would use it's large Poison Barbs as the Drill of course.
Hitmontop: This thing actually has a Drill on it's head that it spins on. Doesn't get much more obvious than that. This move is essentially useless on Hitmontop however, so just for flavor.
Dewgong/Seaking: Both are water types with a horn and no access to earthquake. They both will still suck of course, and it doesn't help them all that much, but it fits.
Cloyster: Same as above, pretty much, except it has Spikes rather than a Horn, and is actually a competent Physical attacker that could make good use of the move, considering the excellent coverage of Ice/Ground.
Nattorei: Like Cloyster, it is a competent Physical attacker with prominent Spikes as a central part of it's design. Nattorei lacks Earthquake, so it would make very good use of Drill Liner in it's place, considering both of it's STABs are walled by Steel and Fire types, and most of it's switch-ins are weak to ground.
Omastar: Similar to Cloyster and Nattorei (they shoot spinning Spikes at high speed) except it has an inferior Attack stat, so mostly for flavor in this case.
Nidoking/Nidoqueen: Also both have horns and are Ground types, so it fits quite well. They both have Earthquake though, so it's purely for flavor.
Rapidash: Another Physical attacker that has a horn but doesn't have Earthquake. Should be able to make good use of this move.
Shubarugo: Has an amazing typing, great defenses, and monstrous attack, but an absolutely barren movepool. Drill Liner fits very well with Shubarugo's Large "Lances" that it also uses for similar attacks like Megahorn. Drill Liner would be a major buff to Shubarugo, giving it a way to hurt Fire Types, particularly Heatran.
