|Boldore||Lv. 27 ~ 28||30%|
|Woobat||/||Lv. 27 ~ 28||30%|
|Aron||/||Lv. 29 ~ 30||20%|
|Axew||Lv. 29 ~ 30||20%|
|Shaking Grass / Swirling Dust||Level(s)||Rarity|
|Drilbur||Lv. 27 ~ 30||100%|
Mistralton Cave 1F
It's quite dark inside of the Mistralton Cave, so you're going to need to use Flash outside of battle in order to light it up. If you don't have Flash, you can pick it up in the alley in Castelia City. You're also going to need to have Strength on one of your Pokemon to move boulders around.
Head south and then push the boulder to the right twice, then down into the hole. Keep going south and then east, running into a Hiker. He's got a Boldore L32. Take him out and then head further east, pushing the boulder into the hole.
There's a Veteran blocking a path in the cave, but you're not going to be able to go that route for awhile, so head on north instead. Further north, the path will branch; head north and down the steps into a little pit to pick up a Dusk Ball, then head back and go west to fight a Hiker. He uses an Onix L32. Just north of him, above the steps, is a Yellow Shard. Go down the steps and push the boulder in the hole to provide a nice shortcut in getting out (and also getting back in).
Head back to where the Hiker is and then head west, over onto that little cliff thing. There's a hidden Super Repel over by the tip, and then there's stairs leading up right beneath the Hiker.
Mistralton Cave 2F
From the start, head north and fight the Ace Trainer there with his Tirtouga L33 and Axew L33. Nothing else up here, though, so head south and down the steps, then push the boulder into the hole with Strength. There's a Green Shard hiding over to the east, but otherwise, take the steps north and then follow the path over to the east.
Heading south from here will eventually lead you to a Hyper Potion, while taking the northern path leads you to a boulder you can shove as well as a Ace Trainer just north of that. She uses an Archen L33 and an Axew L33. Climb up the steps north of her and then follow the edge to find a Blue Shard, while taking the lower path to the north leads you through a path to below where the Ace Trainer is. There's a hidden Ultra Ball right above him.
Go back to the Ace Trainer and then shove the boulder out of the way. Go ahead and shove the second one into the hole, too, to provide quicker access back here for later on. Then go on and climb the stairs to reach the next part of the place!
Just to the west of the entrance is a hidden Full Heal. Head east, but don't go up the steps just yet; instead, head north and you'll find the extremely useful TM80 (Rock Slide), which is a good 75 power Physical-based Rock-type attack that can also cause the foe to flinch. It only has 90% accuracy, but it's still pretty good as far as Rock-type attacks go, plus a lot of Pokemon can learn it.
Anyway, now head back down to the steps and climb up them, pick up the Escape Rope, and then head north. When you climb down the steps to the north, head south and push both of the boulders into the holes. Talking to the old guy doesn't give you anything, but just to the north of him is a hidden Dragon Gem.
If you go west and then north, over to where Cobalion was in the old games, you'll find that it's sadly empty. Yup, there's nothing more to see here. Don't worry, though, as I said earlier, you'll run into Cobalion later on. Don't worry!
Now go ahead and make your way out of the cave, either by using Dig or by using the Escape Rope you picked up (or walk if you feel like it).
Now that you've done all of that, it's time for you to check out the Chargestone Cave and move on with the story! Super Repels are highly recommended to speed up your trip through there.