No waterfalls to climb, just a nice green path to the building itself.
Inside, you'll be able to stock up on the strongest items available, including Full Restores. I'd recommend picking up 15 - 20 Hyper Potions, 5 - 10 Full Restores, 5 - 10 Full Heals, and 10 - 20 Revives. These will all be very helpful against the Elite Four, because they'll give you the opportunity to heal your Pokemon to full so they can be in prime form for each of the master Trainers you'll fight when taking them on.
Additionally, I'd recommend flying back to Goldenrod City real quick and buying some more items to help your fight. As long as you have enough of these items, you should be able to beat the Elite Four under any circumstance as long as you use them properly and have a bit of luck.
What items am I talking about here? The X items, of course! Go ahead and buy 10 - 15 X Defends and X Sp. Defs, 10 - 15 X Speeds, and then 10 - 15 of each X Attacks and X Specials, adjusting the numbers depending on if you use more Physical- or Special-based attacks. If you don't have the money for these, don't worry, just try buy 10 of each, or if that's still unaffordable, get about 5 of each and hope you get lucky.
Lastly, you should give a close look to your Pokemon and think of how you're going to handle each member of the Elite Four and the Champion. Here are some questions you may want to ask yourself:
- Are you using Ho-oh or Lugia?
If you are, they'll be at least level 45, though probably level 47 to 50 by this point depending on how much you used them since you caught them. The challenge factor is significantly less if you're using either of these two Pokemon, and if you use them along with the X items I mentioned, you are almost guaranteed victory. - Are your main Pokemon at level 42+?
I strongly recommend making sure that all of your Pokemon that you're going to be using in the fight (don't bother with HM Pokemon if you use them for that purpose only) are at level 42 or higher. 46+ is recommend, but anything lower than 42 and you're going to be cutting it close. If your Pokemon aren't this strong, make sure that you have plenty of X items, because they can turn any of your matches around if you use them properly! You can also gain some EXP by fighting in the Victory Road if you need a few more levels. (Surf is awesome against all of the Pokemon in there, so try use that.) - How are you going to handle the first Elite Four's Psychic-type Pokemon?
The first of the Elite Four specializes in Psychic-type Pokemon, so this means you'll need to exploit their weaknesses while also resisting their attacks. Dark-type Pokemon are hard to come by at this point in the game, but if you have an Umbreon, you'll be in great shape, as you will be resistant to all of those strong blasts of Psychic. Can any of your Pokemon learn Dark Pulse from TM79? Do any of your Pokemon know Crunch or Bite, or any other strong Dark-type attacks? - How are you going to handle the second Elite Four's Poison-type Pokemon?
The second of the Elite Four uses mostly Poison-type Pokemon, with one odd Bug/Steel-type thrown in there to annoy you with. Do you have any Psychic-type Pokemon (be careful around the bugs) or Pokemon with Psychic-type attacks? They'll do great against his entire team. Ground-type Pokemon or attacks are also very effective against all but one of his Pokemon. Have you taught Earthquake (TM26) or Dig (TM28) to any of your Pokemon yet? - How are you going to handle the third Elite Four's Fighting-type Pokemon?
The third member of the Elite Four uses a bunch of diverse Fighting-type Pokemon. In addition to having strong Fighting-type moves, they also have moves of a variety of types, including one Pokemon whose has Fire-, Ice-, Electric-, and Steel-type punches. Psychic-type Pokemon and attacks are once again your best bet here. Do you have any? If not, are you using any Flying-type Pokemon? HM02 (Fly) is a fair choice for a strong Flying-type attack against these Pokemon. Be wary, though, as two of this Trainer's Pokemon have Rock Slide to punish Flying-types. Lastly, any Ghost-type Pokemon like Haunter, Gengar, or Misdreavus will render this Trainer severely crippled and limited in attacks to hit you with. - How are you going to handle the fourth Elite Four's Dark-type Pokemon?
The last member of the Elite Four focuses on Dark-type Pokemon, though also has two non-Dark-type Pokemon on her team. Her most deadly Pokemon is capable of using Nasty Plot to raise its Sp. Atk sky high, where it will likely one-hit KO any of your Pokemon. Don't focus so much on exploiting the Dark-type's weakness specifically, but just make sure you have a Fighting-, Ground-, or Water-type attack, as well as a Fire-, Flying-, or Ice-type attack, and you should be fine. Do you have these? What will you do if she uses Nasty Plot against you? - What are you going to do against the League Champion's Dragon-type Pokemon?
Lastly, what are you going to do against the League Champion's ultra-strong Dragon-type Pokemon? They all possess powerful moves and have high stats, so they're going to be doing a lot of damage to you. Do you have any Ice-type Pokemon or Pokemon with Ice-type attacks? Avalanche, Blizzard (or Blizzard + Hail for 100% accuracy), and Ice Beam will take out most of Lance's Pokemon with ease. Do you have any Pokemon with these attacks? They're all TM moves. If not, do you have any Pokemon that can learn Dragon Pulse (TM59) or Dragon Claw (TM02) that you recently picked up? Lastly, make sure you have a strong user of Electric- or Rock-type attacks to deal with the League Champion's dragon wannabes.
Does it sound like you can handle them? Do you need more training? Make sure you have everything set before you proceed to fight them in the back of the building, because once you go in, there's no leaving until there's a winner — and that winner might not be you if you're not prepared, in which case you'll forfeit some money! (Though not a lot. You'll usually make it back if you can just beat the first of the Elite Four.)
Are you ready for this?
