YMMV / Pokemon Blue Kaizo

• Demonic Spiders: Pokémon that know Selfdestruct and Explosion, you better be able to kill them in one shot before they get to act or your Pokemon is probably taking a very heavy hit if not being fainted outright, and if your Pokemon fainted you won't get the EXP from the opponent fainting either. Voltorb and its evolution Electrode are the most notable of these Pokémon; their low Attack means their Explosion won't hit as hard as the other boomers, but it'll still leave a severe dent, and with their Speed (including Electrode being the fastest Pokemon in the game by a significant margin), you'll have a very hard time KOing them or escaping them before they explode on your Pokémon. Carrying a high Defense Rock type or a Ghost type on your team to soak up the booms (with the former resisting it while the latter are outright immune) is going to be nigh-mandatory to save you a ton of healing items and Revives over the course of your playthrough.
  • Due to the generally improved natural learnsets, which includes STAB, formerly TM-only moves, and typically a coverage move or two, all Pokemon in general are significantly more dangerous than they were in the original. Additionally stat experience is disabled, so your Pokemon will be mostly on par with opponents of the same level, instead of the significant statistical advantage you would have in the original (you still get the Badge boosts, but it'll take time to get those, and by the end you'll be fighting opponents with Pokemon over level 100 to cancel out the Badge boosts anyway).
  • Anything with at least decent Speed that has OHKO moves, trapping moves, or Sleep-inducing moves. If you're the tiny bit slower, a Pokemon with an OHKO move has a 30% shot to just kill your Pokemon regardless of all other factors, a Pokemon with a trapping move can slowly whittle your Pokemon down and not give you the chance to act unless their move misses, and sleepers can put your Pokemon to sleep before it gets to act, while if your Pokemon wakes up before being KO'd, it can be just put right back to sleep before it can act (plus there's no Sleep Clause like in Pokemon Stadium and competitive PVP, so you can't just switch out the sleeping Pokemon and have the rest of your team be immune to Sleep). These sort of Pokemon are also much more prevalent than they were in the original game, and you could very well lose at some point from just getting unlucky against these moves, especially if your team is predominantly slow Pokemon.
• Goddamned Bats: The one Pokemon that got changes to its base stats in Blue Kaizo? Ditto, with all its base stats being increased to an even 100, making it equivalent to the legendary Mew. Now normally in battle this doesn't matter as all it can learn still is Transform, which copies the opponent's non-HP stats, and overall this gimmick is still quite useless. However this makes Ditto much more annoying in battle, as its drastically faster Speed will make it difficult to run away from if you're not leading with an exceptionally fast Pokemon, and the drastically ramped up durability means it's much harder to kill before it transforms, while after it transforms it'll probably have more HP than your Pokemon if you're not substantially higher levelled, adding to the difficulty of killing it quickly. And then in Gen 1 Ditto gives crappy EXP regardless of if you killed it transformed or not, unlike in later Gens where if it transformed it gave EXP based on the Pokemon it transformed into, giving you little reward for going through the effort of KOing them.
• Goddamned Boss: The second Blue battle on Route 22. He isn't difficult if you get a bigger team and your levels up some first, as all he has is a level 9 Eevee, and a level 8 Mew whose only attacking move is Pound. However his Mew also has Softboiled to recover half of its max HP whenever, and Mew is incredibly durable for your still first stage Pokemon. If you're not very overlevelled, your first stage Pokemon won't come remotely close to 2HKOing Mew to outdamage its Softboils, even with crits, and since the AI has infinite power points you can't rely on Mew ever running out of PP for Softboiled. Then Mew has Thunder Wave too to paralyze your Pokemon for good measure, adding more to the annoyance of killing it. If you try KOing his Mew conventionally while your first stage Pokemon's levels are in the single digits or just breaking 10, you'll get into a very long drawn out battle where you can only win if you get very lucky with A.I. Roulette not picking Softboiled for a long time, and even if that happens Blue has a couple Super Potions, that if he didn't use on his Eevee, he will automatically use on his Mew once its health is low, so eventually you'll probably either get whittle'd down to death by his Pounds or just run out of power points. There is a saving grace against him without having to overlevel, as a few of the available Pokemon at this point start with Toxic, and badly poisoning Mew will guarantee victory as eventually the Toxic poison will outdamage his Softboils if he keeps using it, but if you try that you have to make sure you KO his Eevee first, as otherwise if he switched to Mew before the Eevee went down and you badly poison it, if he switches the Mew back out the Toxic poison will turn into normal poison, which a permanent 1/16th health drain is practically nothing to Softboiled's 1/2 health gain and would then block any additional status.
• Scrappy Mechanic:
  • How much more prevalent Cut trees are in this romhack. In the original RBY there was only three times you had to use Cut to progress, two of which was to access a Gym, and you never needed it again after Celadon. Here, Cut trees are EVERYWHERE, blocking the path forward at so many points, and doing so up until the end of the game. This is especially bad as unlike in RBY you'll actually need a full team to survive in this romhack so you can't really a sacrifice a slot for an HM slave, and since Cut trees persist through the game and block the point forward at so many long routes and block access to many dungeons, you can't make do with a temporary HM slave either, so you'll have to give in and permanently sacrifice one of your Pokemon's moveslots for a crappy move that is already going to be outclassed when you get it.
  • The insane encounter rate in routes and several dungeons, where a random encounter will trigger literally every three or four steps, while routes are often deliberately designed to make you walk through long patches of grass. The developer's reasoning for this is that it makes grinding quicker, while those who don't want the random encounters can just use the nearly-free Repels to not get any, but it is still incredibly annoying that you must use Repels if you want to get through several areas at a reasonable pace, and it isn't a satisfactory solution for those that do want to fight random encounters along the way but at a steady pace of them.
  • Some opponents have a nigh-infinite supply of Full Heals, which due to how Gen 1 AI works will always immediately use them on their turn when their Pokemon is statused, even if they went second. As a result you essentially can't use status moves against these opponents, and if your Pokemon went first, you don't even get the free turn from them using a Full Heal. This removes a good deal of possible strategy against these opponents, especially since it's Gen 1 where Pokemon was at its most primitive and when the dev already removed or restricted access to several other moves and strats in Blue Kaizo. Most frustratingly, all members of the Elite 4 and Champion Blue do this, beating the latter's level 115 Mewtwo without using items yourself is pretty much a Luck-Based Mission when you can't paralyze nor put it to sleep, and don't have any access to stat-buffing moves.
• That One Level:
  • Mt. Moon exemplifies Early Game Hell hard. While your team will be a lot better than it would be in the original, Mt. Moon is even longer here with significantly better trainers that can't be avoided and it's full of wild Pokemon that know Selfdestruct with an even higher encounter rate. The Early Game Hell here is that your funds are very limited at this point, so you won't be able to afford much Potions to keep your Pokemon's health up throughout Mt. Moon, and Revives aren't even available yet, so you'll pretty much certainly end up running out of Potions and getting wiped out if you try going through the mountain in one go on your first try. Progress here will probably entail gradually making a bit of progress and beating a trainer or two at a time before having to retreat back to the Pokemon Center outside to heal up, or going as deep as you can before you get wiped out, until your team gets strong enough to reliably one shot or run away from the boomers and you have all the trainers beaten to make a safe trek through.
  • Route 25, the route between Nugget Bridge and Bill's house north of Cerulean. This is the first time Blue Kaizo employs its "jump down a ledge to go forward and then you can't go back" trick to force you to fight a long gauntlet of trainers, and upon reaching the ledge it's not clear from what you can see that you won't be able to get back until the end of the route, so a first time player will probably go into the route's trainer gauntlet without being adequately prepared, pretty much ensuring they'll get wiped out before finishing the gauntlet without Save Scumming inbetween trainer battles. Then even if you are aware and prepare yourself before tackling Route 25, you won't have any Revives at this point to revive your fainted Pokemon in between battles and your only source of healing is a very limited supply of Potions, so it'll still be very difficult to get through it in one go as one instance of bad luck will knock you down a Pokemon for the entire rest of the gauntlet and you could very well run out of Potions before getting through the route.
  • The old version of Rock Tunnel is notable, due to the lack of HM move Flash, which makes your progress somewhat difficult, coupled with a fairly strong pool of trainers. The Pokemaniacs are particularly dangerous, with generally strong and rare Pokemon.
  • The Safari Zone. In order to get Surf, you need 499 of the 500 available steps, meaning that one mistake will force you to start back from the beginning. The Gold Teeth requires another, separate path that's slightly more lenient, requiring 475 steps at minimum, but also requires you being able to use Surf to reach it.
  • You're forced to go upwards Cycling Road to get Fly, as the old path to the Fly HM west of Celadon has been blocked off by water, while you need to beat Koga first before you can use Surf, and you need Fly to access his gym. Not only is going upwards Cycling Road much slower than going down while you have to deal with the inconvenience of automatically going downward if you're not holding B or moving another direction, it also becomes a maze that requires you to face every trainer, and you'll have to go through a lot of grass full of exploding Pokemon that triggers an encounter every few steps, including the aforementioned Electrode. You also can't access Fuschia City's Pokémon Center until you've gotten Fly, which means that you'll either have to go through it after having already been significantly weakened by the trainer marathon of Routes 12 through 15, or go all the way back to Lavender Town to heal back up and then make the long trek back to Fuschia while dodging the random encounters of Routes 12-15. This also means you have to stock up real well on healing items and Ethers before tackling Cycling Road, as otherwise having to retreat back to the Lavender Pokemon Center to recover health and power points will entail going through that annoyingly long trek again.

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