Head around the coast to the East and pick up a Heart Scale from under the beach sand, and the Draco Plate from the far North end of the beach.  Don’t bother heading into the water, though- that way lies the Pokemon League, for which you are not ready.

Instead, follow Hugh through the North gate of Undella, which leads to Route 13.  The first thing you’ll see here is a martial artist running in circles.

Battle: Black Belt Wesley (1312 Poke)
Opponent: Gurdurr Lv 41

Pass him up and ascend the stairs to the left to find the first patch of Route 13 grass.

Route 13 again provides you with some new opportunities as well as some repeat appearances, all in levels 34-37.  Drifblim makes a reappearance here, as does Absol, but the other four local pokemon are ‘new’.  Tangela is a very old pure-Grass pokemon (the first, in fact) that evolves into Tangrowth with knowledge of the move Ancientpower.  Tangrowth has rather strong defenses physically, but barely has enough Special Defense to get by, and its Speed is a bit on the poor side.  It does, however, have a nice solid Special Attack stat, so it tends to do well against many Fighting types and other pokemon that attack physically and themselves have lacking Special Defense.  It’s particularly noteworthy for possessing Power Whip, a high-power moderate-accuracy physical Grass attack, though it can’t make full use of it with its inadequate Attack.  Still, it’s specialised and not actually bad by any stretch.  Pelipper is here as well, a Water/Flying pokemon that is most noteworthy for its defenses.  Its speed isn’t anything special and while it’s competent with its Special Attack, it’s just not anything to write home about in that regard.  Pelipper has access to the Stockpile-Spit Up-Swallow combination of moves, though, as well as Detect, Mist, Soak, and a number of other status effects.  Last of all, it is one of the few Flying pokemon to naturally learn Hurricane that has a Special Attack worth using with the move.

In addition to these four, the grass on Route 13 contains both Solrock and Lunatone, the Psychic/Rock pokemon that somewhat mirror one another.  Lunatone’s main point is its special attack, and Solrock has stronger physical attack.  Neither of them is terrifically good at anything, though, and their typing sadly doesn’t help them much.  While the highest stat on either is decent, the rest of their scores are from acceptable on down to poor, and neither pokemon really gets access to anything to make up for that.  In essence, these are gimmick pokemon, and not even gimmick pokemon whose gimmicks work well in battle.