|Undella Bay (Spring/Summer/Autumn)|
|Frillish||/||Lv. 25 ~ 40||65%|
|Mantyke||/||Lv. 25 ~ 40||30%|
|Remoraid||Lv. 30 ~ 40||5%|
|Surfing (in surfacing fish)||Level(s)||Rarity|
|Jellicent||/||Lv. 25 ~ 40||60%|
|Wailmer||Lv. 25 ~ 40||30%|
|Mantine||/||Lv. 30 ~ 40||5%|
|Wailord||Lv. 30 ~ 40||5%|
|Undella Bay (Winter)|
|Frillish||/||Lv. 25 ~ 40||65%|
|Spheal||/||Lv. 25 ~ 40||30%|
|Remoraid||Lv. 30 ~ 40||5%|
|Surfing (in surfacing fish)||Level(s)||Rarity|
|Wailmer||Lv. 25 ~ 40||60%|
|Sealeo||/||Lv. 25 ~ 40||30%|
|Walrein||/||Lv. 30 ~ 40||5%|
|Wailord||Lv. 30 ~ 40||5%|
Mantyke and Mantine are both Water/Flying-type Pokemon, giving them a huge weakness to Electric-type attacks and a decent weakness to Rock-type attacks, but other than that it's pretty balanced out. Mantyke evolves into Mantine when it gains a level with Remoraid in your party, which you have to catch separately (and it's rare and hard to find, too, at least until after you've beaten the game). That makes it a pain to evolve Mantyke, but you're obviously going to want to evolve it as soon as possible. As a Mantine, it has a massive amount of Special Defense, but then pretty average other stats. Its Speed is mediocre. Its Special Attack is enough to attack with, but nothing to get too excited about. Its Defense isn't great, but it's also not terrible, either. It has either the Swift Swim or Water Absorb ability. Swift Swim doubles its Speed in the rain, which is pretty nice, while Water Absorb gives it an immunity to Water-type attacks and restores its HP by 25% of its max whenever it is hit by one. Both are pretty good for it.
For moves, it has an interesting assortment. Confuse Ray (level 11) is helpful to confuse the foe and potentially give Mantine more uninterrupted attacks. Water Pulse (level 19) is a good compromise to that, because it hits for some mild Water-type damage but has a 30% chance of confusing the foe. Wide Guard (level 23) is very helpful in Double and Triple Battles, particularly against other players, where it protects your whole team from moves that target more than one Pokemon. Agility (level 32) raises its Speed, but the Swift Swim variant prefers using Rain Dance instead. Air Slash at level 36 is actually a nice move for Mantine and has a 30% chance of causing the foe to flinch, which helps compensate for its low Special Attack. At level 49, it gets Hydro Pump for massive damage, albeit with less accuracy. You can use Heart Scales to reteach Signal Beam and Psybeam for some odd moves, should you so desire them.
Surf is an important HM move for Mantine, but Scald is also very handy for it, too, since it has a high chance of burning the foe, thus crippling their Attack (which is something Mantine's high Special Defense can't deal with). Rain Dance is good for raising the power of its Water-type attacks as well as raising its Speed thanks to Swift Swim (if you go that route). Lastly, Ice Beam is a great move for it to learn when you have access to it.
There are several problems with Mantyke and Mantine. The fact you have to find a Remoraid to get it to evolve is a real pain. Its attacking stats and Speed are low. And it doesn't really have anything remarkable that set it apart from the other great Water-type Pokemon you have access to, such as Vaporeon or Starmie, aside from that Special Defense, which won't matter most of the time. It's sort of like the Special-based Skarmory of the sea, but much worse.
Remoraid and Octillery are an interesting duo of Pokemon that have the equivalent of a swiss army knife as far as attacks go. Both are pure Water-type. Remoraid evolves at the mere level 25, which isn't too bad at all. As an Octillery, it has pretty darn good Attack and Special Attack, slightly above average HP, Defense, and Special Defense, but pretty dismal Speed. It has either Suction Cups (or Hustle as a Remoraid) or Sniper. Suction Cups prevents it from being forced to switch out by attacks like Roar, Whirlwind, or Dragon Tail, while Sniper increases the damage its critical hits do from 2x the usual to 3x the usual, making them rather lethal. Sniper is definitely preferred.
For attacks, it will have access to a lot of good ones right from the start. Water Pulse, Signal Beam, and, most importantly, Ice Beam are all possibilities for it around the time you catch it (between level 30 and 40; it gets Ice Beam at level 34 as a Remoraid, or 40 as an Octillery, though). Focus Energy is also a move it'll have, and even though I don't usually recommend or mention it, the Sniper ability just hits so strong that it's worth boosting your odds of it as much as possible. Between Focus Energy and equipping the Scope Lens, you'll give Octillery a 25% of hitting a superpowerful critical hit. That being said, while Bullet Seed (level 38 as Remoraid or 46 as Octillery) may not be immediately interesting (2-5 hits at 25 power a pop; Grass-type, Physical-based), consider that each of those hits has a chance of a critical hit, and you may be in business. It gets Hydro Pump at level 52 and then some unnecessary moves as it levels up further (Hyper Beam and Soak). You can invest some Heart Scales in order to reteach some more moves. Gunk Shot (120 power Physical-based Poison-type attack) is an odd, though inaccurate move for it. Psybeam is weird, but it gets Psychic via TM shortly after you catch it. Rock Blast is a good move for some Rock-type coverage and gives better coverage than Bullet Seed does. Lastly, its signature move, Octazooka, hits for a fair amount of power, but has a 50% chance of lowering the foe's accuracy afterwards. It's not all that great, really.
Octillery gets access to a ton of TM moves. Surf (HM) is the most obvious must-have choice for it. Oddly enough, it gets access to Energy Ball, Flamethrower (!?), Psychic (!?), and Ice Beam (yeah!). These are all pretty good attacks; Energy Ball would be the one to ditch, though, if you had to pick. Charge Beam is a possibility for an Electric-type attack that can also raise its Special Attack by one stage, while Scald hits lighter than Surf, but has a chance of burning the foe and is safe to use in Double or Triple Battles. Thunder Wave can be good for slowing the foe down, since Octillery is very slow.
Compared to all of the other Water-type Pokemon out there, Octillery is definitely among the slowest, but it also has some really good attacking stats and reasonable defenses. What's most fun about Octillery is its huge movepool of interesting and unique attacks. Where else are you going to get Flamethrower on a Water-type Pokemon? Starmie still outclasses it and is still very diverse. Options like Simipour and Vaporeon are also probably better, but Octillery isn't so bad if you can just get over that Speed problem. Sadly, that's a pretty big problem that's hard to overcome, limiting its overall usefulness. However, the fact that it gets Ice Beam before the upcoming Gym and is not an Ice-type Pokemon makes it a worthwhile choice against the Gym, since it packs counters to Ice-type Pokemon, but not Water-types.
The giant of the sea, Wailord is indisputably the largest Pokemon out there, dwarfing most other Pokemon in size (it's over 47 foot long!). It evolves from Wailmer at level 40, so you may have to do some leveling up before you get one, unless you happen to catch a Wailord that's already set to go, which is possible. Wailord has the 4th highest HP in the game — not Unova, but in the whole game, behind only Wobbuffet, Chansey, and Blissey. It has the highest HP in all of Unova, though. Its Attack and Special Attack are... slightly above average, but still rather underwhelming. Defense and Special Defense? Awful. And it's Speed is definitely below average, though it thankfully isn't sluggishly slow. It has either the Water Veil or Oblivious ability. Water Veil prevents it from being burned while Oblivious prevents it from being attracted. Neither are that great, although Water Veil will probably help slightly more.
For moves, depending on when you get it, you'll have a different assortment of starting moves. Nothing early on is really worthwhile, though, but Water Spout at level 34 is rather impressive at first glance. It has a monstrous 150 power, but its power goes down drastically as Wailmer and Wailord's HP becomes lower, so it's only really effective if it's at full HP. Amnesia at level 37 helps fix its low Special Defense problem by raising it two stages, which can be a help, but it won't save the day. It gets Dive naturally at level 46 (as a Wailord; it's level 41 as a Wailmer), but remember, you can't just forget it since it is an HM move, so learn it only if you want it. Bounce at level 54 is interesting for a Flying-type attack, but generally unnecessary. Hydro Pump at the distant level 62 is powerful, but its accuracy leaves much to be desired. You're better off with Surf. Lastly, it gets Heavy Slam at level 70, which does more damage depending on how heavy Wailord is compared to the foe, and since Wailord is pretty heavy, it'll probably hit pretty hard.
Surf is a must-have TM move (well, it's technically an HM move). Bulldoze is a good move to consider for it, since it lowers the foe's Speed by one stage, putting it in perfect range for Wailord to squeak out a second attack afterwards since that Speed reduction will probably slow it down just enough. Ice Beam is good later on for it, while Scald can be a good alternative to Surf that also has a chance of burning the foe (30%). There are a few Move Tutor moves worth considering, too. Iron Head for 4 Red Shards in Driftveil City is alright if you need a Steel-type attack (but you probably don't). Icy Wind for 6 Blue Shards in Lentimas Town is like Bulldoze, except it's a Special-based Ice-type attack instead (and it hits only the foes), while Zen Headbutt (8 Blue Shards) gives it access to a Psychic-type attack.
Even though Wailord's HP seems high, the rest of its stats really just don't give it anything to sing about, and that high HP is quickly diminished by its poor defenses. That doesn't give it as much durability as you'd think. You're MUCH better off with Vaporeon if you're looking for a bulky Water-type with high HP. I really can't recommend Wailord. It also isn't diverse enough to give it much to separate it from other Water-types, either.
The trio of Ice-types from Hoenn make a return in Black 2 and White 2, although only in the winter. Spheal can be found just by surfing around, while both Sealeo and Walrein can be found if you surf into the rippling water. Spheal evolves into Sealeo at level 32, then into Walrein at level 44. Once it becomes a Walrein, it has some pretty well-rounded stats, except has some below-average Speed and well-above-average HP. Its defensive stats are pretty good to go with that HP, giving Walrein some nice bulk and resilience. It's hard to take down for that reason. Its abilities are Thick Fat or Ice Body. Thick Fat reduces the damage it receives from Ice- and Fire-type attacks by 50%, which is nice (and makes it so Ice-type attacks do a mere 1/8 their usual damage against it, haha), while Ice Body heals its HP by 1/16 its maximum between turns if it is hailing. Thick Fat is definitely preferred, because the healing is minor, although coupled with Leftovers and it heals a pretty decent share while whittling away at the foe's HP.
Some moves that it may have are Body Slam, which is a decent Normal-type attack that has a 30% chance of paralyzing the foe. Not too bad to start off with. Aurora Beam is one of the main Ice-type attacks it has, because it, sadly, doesn't get too many useful ones. Hail at level 31 is nice to learn naturally and helps do damage to the foe, heal its HP if it has Ice Body, and also boost Blizzard's accuracy to 100%. At level 32 as a Sealeo, it gets Swagger, which confuses the foe but raises its Attack by two stages, meaning it will hit both you and itself much harder. It's a gamble, but one that Sealeo and Walrein can usually afford to take. Rest and Snore, at level 39, work surprisingly well with Leftovers, Ice Body, and Hail to just sit back and whittle away at the foe's HP while keeping your own HP satisfactory, although you'll have to keep resetting the hail every couple of turns. When it evolves to Walrein at level 44, it gets Ice Fang, which... well it's kind of underwhelming of an option, really, since even Aurora Beam will hit harder. Blizzard at level 52 is alright, but you also get a TM for it. You can take it back to the Reminder Girl and have her teach Crunch after it's evolved to Walrein, and that's a pretty nice attack for it.
For TMs, Surf (HM) is yet again an obvious choice for it and is a must-have move for it. Rock Slide and Bulldoze are also two decent moves for it that you have at this point, although they work off of Walrein's lesser Attack stat. Ice Beam is excellent once you get it, but don't count on getting it before the 7th Gym, because you don't until after the 8th Gym, sadly (at least you get it before beating the game). For Move Tutor moves, it has some more options: Iron Head and Signal Beam are both options for just 4 Red Shards in Driftveil City, while Icy Wind, Iron Tail, and Aqua Tail are all options for 6 or 8 Blue Shards in Lentimas Town. Icy Wind is nice because it often drops the foe's Speed by just enough to give Walrein the edge, making up for its low power.
All things considered, Walrein is still the best Ice-type you can get at this point. However, before too long, you'll have access to the even better option, Lapras, which is definitely better than Walrein and (a little) less of a hassle to get. But since Ice-type Pokemon are hard to come by, give it some consideration at least.
On the northeast shore of Undella Bay, you can use your Dowsing MCHN to find a hidden Heart Scale. Neat. There's also a Draco Plate further north of that, which boosts the power of the holder's Dragon-type attacks by 20%. Now hit the sea and get ready to fight a whole ton of Water-type-using Trainers!
The Swimmer ♂ right near the Draco Plate has a Mantyke L39 on his team. Just north of him is a Swimmer ♀ with an Alomomola L39. There's a cave right past her, but it's blocked off by a guy and his pack of Roggenrola. You can actually find Seel, Tynamo, and Golduck if you run around in there, but I'll cover that area later, as you'll be back. It's the Seaside Cave.
To the east of the Swimmer ♂ is a Swimmer ♀, and she uses a Spheal L38 and a Wailmer L38. Further east leads to a dead end, with a suspicious black hole in the water. What's that for? That's for where you can use Dive to dive underwater in, but you won't be able to get the HM for Dive until after you've beaten the game.
Diving to be Rich!
Just because you don't get HM06 (Dive) until after you've beaten the game doesn't mean you can't go diving, even without trading! Two Pokemon you can find in the area — Wailmer and Seel (found in the Seaside Cave north of Undella Bay) — both learn Dive naturally at level 41 in their unevolved state (or later in their evolved state).
If you feel like making a fortune, train one up to level 41 (Everstones are helpful to keep them from evolving) so it learns Dive, then use it on the dark blue patch of water. You'll be able to explore the Abyssal Ruins, which holds a whole ton of the Plate items on the first floor, which raise the power of the respective type's attacks by 20%, as well as a whole ton of Relic Loot, which can be sold to the Black Belt in the westernmost house in Undella Town for a fortune. If you gather up all of the loot (which may take awhile and several attempts), you can sell it to him for over $2,000,000, which should be more than enough money to buy whatever you want.
I'll cover the Abyssal Ruins more in-depth in the post-game section of the walkthrough, but in my initial testing, it seems to at least have the same layout as in the original Black / White Abyssal Ruins. If you're feeling adventurous, check out the Abyssal Ruins section of the Black / White Walkthrough, which should help out a bit (even though it's for the original games).
Go on west and you should find a Swimmer ♂ that uses a Basculin L39. Keep going west until you find the shore again, then head a little south and you'll find some shallow water you can land at. There's an Ace Trainer there with a Pelipper L40 and a Starmie L40. She's right near a Splash Plate, which is another one of the Plate items that boosts a Pokemon's Water-type attacks by 20%.
Head east from her and you'll find yet another Swimmer ♂. This one uses a Sealeo L39. He's the last one you have to fight, though, and pretty much the only thing left to do here.
At this point, you can either head south of Undella Town to Route 14 if you haven't done so already to pick up some extra loot, or you can just go ahead and proceed to Route 13 to the north of Undella Town to continue on your adventure. The choice is yours!