Route 31 Enc. Rate: 25
Wild Pokemon		Type(s)	Level(s)	Morn.	Day	Night
	Pidgey	/	Lv. 3, 5 EXP: 23 ~ 39	30% 10%	30%	0%
	Ledyba	/	Lv. 4 EXP: 30	0% 30%	0%	0%
	Caterpie		Lv. 4 ~ 5 EXP: 30 ~ 37	35% 0%	35% 0%	0%
	Weedle	/	Lv. 4 ~ 5 EXP: 29 ~ 37	0% 30%	0% 35%	0%
	Bellsprout	/	Lv. 3 EXP: 36	20%	20%	20%
	Metapod		Lv. 5 EXP: 51	15% 0%	15% 0%	0%
	Kakuna	/	Lv. 5 EXP: 50	0% 10%	0% 15%	0%
	Spinarak	/	Lv. 3 EXP: 23	0%	0%	30% 0%
	Hoothoot	/	Lv. 4 ~ 5 EXP: 33 ~ 41	0%	0%	10% 40%
	Rattata		Lv. 4 ~ 5 EXP: 32 ~ 40	0%	0%	40%

Trainers at Route 31
	Bug Catcher Wade			$32
		Caterpie		Lv. 2 22 EXP
		Caterpie		Lv. 2 22 EXP
		Weedle	/	Lv. 3 33 EXP
		Caterpie		Lv. 2 22 EXP
* Wade will offer their phone number after the fight.

Items at Route 31
	Potion Directly to the west of the Dark Cave.
	Blk Apricorn Right by a man and a Bug Catcher near the end of the route.
	Poke Ball Near Bug Catcher Wade.

A new Pokemon you can fight on your way to Violet City is Bellsprout. Though it won't be overly helpful against the first two Gyms (Flying- and Bug-type Pokemon), you can trade it in Violet City for an Onix, which might be of more use to you in those Gyms.

Rather soon into the route, you'll find a cave just sitting there. That's the Dark Cave, and there's not really a whole lot you can do there now — not to mention it's really dark inside! But you can fight Zubats and Geodudes inside and there's also a Potion inside.

You can explore the Dark Cave after you've gotten TM70 (Flash) and, preferably, HM06 and the Zephyr Badge from Falkner in Violet City so you can use Rock Smash on the rocks.

Of course, there's also a Potion right outside of the cave anyway, so it's almost kind of silly going in.

Head along west to find a Poke Ball and a Bug Catcher waiting for you right before the entrance to Violet City.