Hoppip is available only during the morning and day on Routes 13, 14, 15, 32 and 33 in GS, with Crystal adding Hoppip in the morning and day to Routes 11, 29, 30 and 31. Skiploom is available only during the morning and day, on Route 14 in all three games.
Hoppip is a Grass/Flying type and it does not receive Flying STAB moves in Generation II. And as its Grass typing isn't particularly good in Johto, you'll need a good strategy to use it well. You probably won't use one caught in Kanto as you're less likely to need team members towards the end of the game, but its typing works better in that region. Hoppip isn't the best Pokémon to use, but it's not completely worthless thanks to an above-average Speed stat and decent Special Defense. The Hoppip Line is better suited to players that enjoy stall, as its moveset is filled with status, set up and recovery moves and it has little offensive presence. This also makes it great for catching new Pokémon.
Note: It is recommended that you keep your Hoppip or its evolutions from battling any gym leaders until Morty. This is because of poor type matchups with Falkner and Bugsy and insufficient bulk to deal with Whitney.
Gym #1 - Falkner (Violet City, Flying-type): Hoppip should not enter this battle if there is a better alternative. Even though Falkner’s Pidgey does not carry Flying STAB, your options to attack it will be Splash, Synthesis, Tail Whip and Tackle at most. Falkner’s Pidgeotto can hit pretty hard with Gust, being a second stage Pokémon. Avoid battling it with Hoppip.
Gym #2 - Bugsy (Azalea Town, Bug-type): Again, Hoppip should not enter this battle if there is a better alternative. While its Flying type means that it takes neutral damage from Bug moves, you should not expect to survive STAB moves from his Scyther easily. Or at all. If you aren’t overleveled, you will not have evolved yet either.
Rival (Azalea Town): Nothing you do will be able to touch the Rival’s Gastly. If you really, really, really want to, you can Tackle-spam the Zubat, but this is risky, because it has neutral Bite and will be faster. It can flinchhax. Obviously, Quilava should be avoided. Croconaw and Bayleef are more harmless, and can be stalled out with PoisonPowder if you want to play THAT game. Croconaw is much easier to stall. Bayleef is like a mirror match, but it doesn’t have recovery moves and you 4x resist its Razor Leaf, so this will be relatively simple as well.
Gym #3 - Whitney (Goldenrod City, Normal-type): Once more, Skiploom should not enter this battle if it is avoidable in any way. If you must use Skiploom, avoid using it for the Clefairy, as it can Metronome any of Skiploom’s 5 weaknesses or explode. This battle is easier for Skiploom in GSC than in HGSS, because Whitney’s Miltank does not have a Lum Berry in this game and a female Skiploom can wear it down with PoisonPowder or render it useless with Sleep Powder. That said, you should watch out for super-effective Rollout gaining power and missing the 75% accurate status moves. One option is to status it and switch, but ensure that the Pokémon you send in next resists both Normal- and Rock-type moves.
Rival (Burned Tower): This fight is only a little harder than the last Rival fight. By now, you should have Leech Seed, allowing you to wear down his Haunter without much trouble if you want to. Avoid using Synthesis because it has Spite. Your Skiploom should be faster than his Zubat, so if you want to take revenge for the Bite-flinches, you can Leech Seed that too. Magnemite has SonicBoom and Quilava should be avoided because it has Ember. The strategy for Croconaw and Bayleef remains the same.
Gym #4 - Morty (Ecruteak City, Ghost-type): At this point, it is suggested that players get a Quick Claw from National Park to give to your newly evolved Skiploom. Though Skiploom cannot do much in this battle, it is able to Sleep Powder Morty's Gengar. The Quick Claw gives it a 20% chance to outspeed. Be warned that Gengar is faster than Skiploom and has Hypnosis to mirror your status. Shadow Ball also hits far harder than you want it to. If you choose to use Skiploom in this battle, quickly switch out after statusing and get your MVP for this battle to KO The Gengar, the hardest part of Morty's battle. You should have Leech Seed by now, so if you’re desperate for EXP, Morty’s Gastly is relatively harmless for Skiploom to take on.
Eusine (Cianwood City, Crystal only): Drowzee’s only threat is the Hypnosis and Dream Eater combo. If you manage to put it to sleep first, and then sap off its health, you should be golden. Don’t use Skiploom or Jumpluff against his Haunter, as it could Mean Look and Curse you, making you waste many healing items. Electrode has Thunder, and is much too strong.
Gym #5 - Chuck (Cianwood City, Fighting-type): If you evolve Skiploom and level it a little, it can serve as a hard counter to Chuck's Poliwrath, a Water/Fighting type. Buy some Awakenings from Ecruteak City. Chuck’s Poliwrath carries Hypnosis, but will not do too much damage otherwise. Use Sleep Powder on the Poliwrath and take care of the Primeape with another Pokémon. Then switch into another Pokémon and use Jumpluff to stall if necessary. Note that Jumpluff does not have the best physical Defense, so you should probably be slightly overleveled to take STAB DynamicPunches well.
Gym #6 - Jasmine (Olivine City, Steel-type): Jasmine has two Magnemite and a Steelix. While Jumpluff can technically battle both Magnemite, since Thunderbolt is neutral, I wouldn’t trust it to survive critical hits and Thunder Wave is too annoying for it to be worth it. Steelix has a super-effective physical move and a 100 BP STAB move and you should avoid battling it with Jumpluff.
Rocket Executive battle #1 (Team Rocket HQ): This Executive has a Zubat, Koffing and Raticate. The Zubat cannot damage Jumpluff too badly, but you will need Leech Seed and Sleep Powder to battle it without confusion hax and crits. Avoid fighting the Koffing and the Raticate. The Koffing has Selfdestruct, and the Raticate is a threat with STAB Hyper Fang and Quick Attack.
Rocket Executive battle #2 (Team Rocket HQ): She has an Arbok, a Gloom and a Murkrow. Avoid fighting all three. The three Electrode you have to fight also have Selfdestruct, so it’s worth it to forgo your catch for the Rocket Hideout if you don’t have something to tank the hit. Jumpluff cannot.
Gym #7 - Pryce (Mahogany Town, Ice-type): No. Just no.
Rocket Executive battle #3 (Goldenrod Radio Tower): He has 5 Koffing at level 30 each and a Weezing at level 32. It’s obvious that this is not the battle for Jumpluff. Their ability to explode is even worse than their Poison typing.
Rival (Goldenrod Underground): Silver’s new team sees some evolutions since the last Rival fight. Jumpluff can no longer safely take on his Golbat with the addition of Wing Attack to its moveset. His Magnemite becomes easier to defeat by Sleep-Seeding, though it can be annoying to deal with Thunder Wave and Supersonic. Haunter is a little trickier this time around, with Mean Look and Curse to wear down your Jumpluff’s HP, but if you kept Leech Seed and Synthesis, you’ll still be fine as long as Magnemite didn’t paralyze you. Sneasel, surprisingly, also cannot do much damage to you as it only has a weak Dark-type STAB coming off its weaker attacking stat. Careful of Quick Attack though, as Leer and Screech can stack up. Avoid battling Quilava for obvious reasons. Feraligatr should be easy to stall, still. Meganium is a much worse mirror match now, as it packs Synthesis and you can’t Leech Seed it. It’s only possible to battle it if you’ve kept PoisonPowder till now and you don't have a healing limit.
Rocket Executive battle #4 (Goldenrod Radio Tower): This Executive has an Arbok, a Vileplume and a Murkrow. Believe it or not, it is actually perfectly safe to Leech stall the Arbok with Jumpluff, since even at your unluckiest, 3 critical hit Poison Stings won't kill. Just remember to heal when it starts using Wrap or if you get poisoned. Vileplume and Murkrow are far more dangerous and should be avoided.
Rocket Executive battle #5 (Goldenrod Radio Tower): He has a Houndour, a Koffing and a Houndoom. Avoid all three.
Suicune (Bell Tower, Crystal only): It's a level 40 legendary with Gust. It's not wise to try it, but if you're trying to catch it, you can take some hits just to put it to sleep. That's only if you're at similar levels though.
Gym #8 - Clair (Blackthorn City, Dragon-type): This gym can be quite like Russian roulette, so try to use another Pokémon here. Clair has 3 Dragonair, one of them has Ice Beam and the others with Surf and Thunderbolt can be battled by Jumpluff. If you’re certain that the Dragonair Jumpluff is currently facing does not have Ice Beam, then you can battle it, but it will be a status move stallfest. It is not recommended that you use Jumpluff to battle her ace, Kingdra, but you can Sleep Powder it before switching if your team lacks hard counters to Kingdra, Jumpluff can also Leech Seed to combat its Smokescreen strategy and slowly drain it. Even in this case, another Pokémon should be sent out to stall damage after setting up since Jumpluff should not take a Hyper Beam from a Kingdra.
Rival (Victory Road): Silver’s Victory Road team remains much the same, by which I mean trouble for Jumpluff. Sneasel is suddenly more dangerous as Fury Cutter's damage adds up. If you must fight it, put it to sleep or face the consequences. Golbat should not even be attempted, as it carries STAB super-effective Wing Attack for Jumpluff. Magneton hits a little harder now, but it's still easy to Sleep-Seed it if you don't allow damage to rack up. Haunter can wear Jumpluff down with a Mean Look and Curse combination, along with Shadow Ball. But if you don't have a healing limit and you get a Leech Seed on it, you'll outlast it. Your strategy for the fully-evolved starters remains exactly the same as in the previous rival battle. Avoid Typhlosion, Feraligatr is pretty easy with Sleep-Seed. Meganium will be long and drawn out since it is a mirror match. You'll want to PoisonPowder and get out, if anything. Kadabra can be battled if you're playing Set Mode, since a switch is far more dangerous than leaving Jumpluff in, but a strong physical attacker is typically better to fight it.
Elite Four Will (Indigo Plateau, Psychic-type): At first glance, Will's whole team spells trouble for Jumpluff, but some parts of this battle are manageable. Jynx should be avoided completely as STAB super-effective Ice Punch will definitely OHKO your Jumpluff. Slowbro can also use Jumpluff as a set up opportunity, so avoid it as well. Will's Exeggutor and his pair of Xatu are really bulky and can hit reasonably hard, but if you're careful, they can be managed with PoisonPowder and Leech Seed respectively. Put both Xatu to sleep if you want to attempt this.
Elite Four Koga (Indigo Plateau, Poison-type): Ariados only has Giga Drain for damage, so it's probably an easy KO for Jumpluff. That said, it also has Double Team and Baton Pass. Since Jumpluff cannot reliably eliminate the rest of Koga's team, it's better to get rid of Ariados more efficiently with another Pokémon. Venomoth has Gust as well as Toxic and Supersonic, so it is best avoided unless you have absolutely no other options. Forretress has Explosion, which no Jumpluff wants to take. Muk and Crobat are a no as well, they both have strong, super-effective STAB moves.
Elite Four Bruno (Indigo Plateau, Fighting-type): Hitmontop cannot touch Jumpluff, so if you play with Battle items, you can set up X Attacks or something for Headbutt, or even just enjoy slowly killing it with your tiny ball of fluff. Hitmonchan is much more dangerous with 4x effective Ice Punch and should be avoided. Hitmonlee does more damage than Hitmontop, but Hitmonlee can also be managed with Sleep-Seed if you brought a lot of heals or Synthesis. Onix and Machamp have Rock Slide. Avoid them both.
Elite Four Karen (Indigo Plateau, Dark-type): Umbreon can trap Jumpluff with Mean Look, and spam Sand Attack to be annoying, but once you have Leech Seed on it, and maybe PoisonPowder, it's only a matter of time. Skip Vileplume, since it has STAB super-effective Acid. Murkrow lacks Flying STAB, so you can go ahead and stall it too, for as long as it doesn't Whirlwind you out. Gengar can Curse and Destiny Bond, but no real damage moves otherwise, so it can be stalled out too, but Leech Seed might take a while. Houndoom has Flamethrower, so lolno. Don't even try it.
Champion Lance (Indigo Plateau, Dragon-type): The only things Jumpluff can take on here safely are the Thunder Dragonite and Gyarados. However, both have Hyper Beam (which Jumpluff will definitely not take nicely) and there are also two level 47 Dragonite with Blizzard and Fire Blast respectively, so you can’t be sure if fighting one is safe for Jumpluff until it uses its coverage move. Everything else can hit Jumpluff super-effectively, usually either 4x or with STAB. Also, the ace Dragonite has Safeguard, so better status fast if you’re risking a Fire Blast to the face to take it on.
From this point onwards, you can fight the gyms in any order, though you will need to retrieve the Machine Parts from the Cerulean City gym before you have access to the earlier portion of Kanto. Feel free to anticipate or postpone any battles as needed.
Jumpluff does not fare as badly in Kanto as it does in Johto, as the former region is not as aggressive towards Grass-types. In fact, some of the gyms are quite kind to Jumpluff. The recommended order for Jumpluff users is Janine > Erika > Brock > Misty > Surge > Sabrina > Blaine > Blue. This order allows you to get the Toxic and Giga Drain TMs before Brock and Misty and gives Jumpluff much-needed levels before some of the trickier matchups. Maybe also pick up Protect from the Celadon City Department Store if you really want to have fun with this.
Gym #9 - Brock (Pewter City, Rock-type): This should be the easiest gym battle you've ever done with Jumpluff. Literally all you have to do is Giga Drain five times and you've won. Most of Brock's Rock types don't even have Rock type moves, but even if they did, you outspeed them and they're all quadruple weak to grass and about 10 levels under your Jumpluff by now.
Rival (Mt. Moon, optional): Suddenly Silver got a lot more threatening. Golbat sticks with the same moveset, but if you haven't been keeping up with the level curve, you're in trouble now. Avoid fighting Golbat. Magneton is still perfectly safe. Silver's Haunter evolved, meaning you definitely want some other Pokémon to be taking those STAB Shadow Balls now, even if they are physical in this gen. Sneasel is still high risk high reward with Fury Cutter. Alakazam is much more deadly than Kadabra, so you'll want to OHKO or 2HKO it, which Jumpluff cannot do. As usual, Typhlosion should be avoided and Feraligatr is safer than ever with Giga Drain on your side. One notable difference is that Silver's Meganium gets rid of Synthesis here, making that battle much easier for your Jumpluff.
Gym #10 - Misty (Cerulean City, Water-type): You should fare pretty well against Misty except for Lapras and Starmie, where you should switch out into a Pokémon with high Special Defense and try to keep some healing items on you. Both carry some pretty powerful Ice type moves in Blizzard and Ice Beam.
Gym #11 - Lt. Surge (Vermilion City, Electric-type): Raichu can be stalled out if you want to, especially if you have the holy trinity of Toxic, Leech Seed and Giga Drain. Both the Electrode can use Explosion, so switch Jumpluff out for them. Electabuzz has Light Screen and Magneton has Lock-On and Zap Cannon. You can fight them if you have Sleep Powder, though be wary of its miss rate. Magneton in particular can be annoying with Double Team.
Gym #12 - Erika (Celadon City, Grass-type): Avoid Victreebel due to STAB Acid, but feel free to poison-stall the rest, as they only have Grass moves and you now have Toxic! Or possibly still PoisonPowder. The point is that Jumpluff will have fun in this gym and you finally get a decent STAB move through the Giga Drain TM.
Gym #13 - Janine (Fuchsia City, Poison-type): Despite the low levels, everything here is a terrible matchup due to super-effective STAB and resistance to Grass, plus the immunity to poison status. Jumpluff can only hope to seed-stall the Ariados as it only has Giga Drain, but it loses to everyone else. The only reason you're doing this gym first is to get the Toxic TM. Much better than PoisonPowder.
Gym #14 - Sabrina (Saffron City, Psychic-type): Everything on her team is much too strong to go down to Jumpluff, and will probably take down Jumpluff easily. That said, considering the level difference at this point, this battle is possible, but not recommended. It's better to use a strong physical attacker here.
Gym #16 - Blue (Viridian City): It's best for Jumpluff to only OHKO Rhydon and possibly attempt to stall the Exeggutor, as everything else on Blue's team is either too powerful or too resilient to Jumpluff's moves for it to do anything useful against them.
Rival (Indigo Plateau, optional): Much like the previous battle, as the Pokémon have changed very little. However, Golbat is a Crobat now, which is one more reason to avoid fighting it. For the other matchups, refer to the Mt. Moon battle.
Red (Mt. Silver): Jumpluff can only hope to see some use against Pikachu and Venusaur, and only by stalling the first and directly attacking the second, which cannot be poisoned. The rest is either too strong for Jumpluff to take on (Espeon), has supereffective coverage against it (Charizard and Blastoise), or Rest to nullify the Toxic status (Snorlax).
Hoppip starts off with Splash, and also Synthesis in Gold and Silver, but it learns it at level 5 in Crystal. At that level, it also learns Tail Whip. The first damaging move the line sees is Tackle at level 10, and that's also the only one it gains via level up; PoisonPowder comes at level 13, then Stun Spore at 15, and later Sleep Powder at 17. This concludes the powder moves learning spree; keep whichever you like of them, or all three if you want to and have room. After evolving, it gets Leech Seed at level 22, which is a very useful move for its primary purpose: stalling. It then evolves into Jumpluff, and learns the next move at level 33, Cotton Spore; this is useless as Jumpluff's Speed is already more than high enough. The last level-up move is Mega Drain, which comes at 44; it is also the only other damaging move it learns after Tackle, and the first and only STAB move learned by level.
Via TM, it gets access to the very useful Headbutt, whose flinch rate helps greatly with stalling techniques; it is possibly the best move it learns. Protect works in a similar fashion, allowing to gain a free turn every two after the opponent has been poisoned and/or seeded, though this is only available in Kanto. Giga Drain, the only decent STAB it gets, is sadly also postgame-only. For lovers of dangerous games, it is possible to attempt stall-seeding with Double Team or Attract.
A paraflinch moveset with Stun Spore, Headbutt and Leech Seed is viable.
Minimum stats are calculated with 0 EVs, IVs of 0, and a hindering nature, if applicable.
Maximum stats are calculated with 252 EVs, IVs of 31, and a helpful nature, if applicable.
Hoppip Line Ratings
At what point in the game should I be evolved? It should be evolved as soon as it is possible. No moves are exclusive to pre-evolutions.
How good is the Hoppip line in a Nuzlocke? Grass-types don't fare very well in Johto and it is not advised that you use the Hoppip Line if you have better options. However, Jumpluff’s Speed stat makes it a very useful status move user in a pinch. In Kanto, Jumpluff has better type matchups and usage is similar but not identical to using a Grass-type like Bulbasaur in FRLG Kanto.
Weaknesses: Flying, Poison, Rock, Fire, Ice (x4)
Resistances: Fighting, Water, Grass (x0.25)
Neutralities: Normal, Bug, Ghost, Steel, Electric, Psychic, Dragon, Dark