Part One: Evil Castle

- The first thing to note is the ‘Swamp’ chapter. It is short, and you are apparently a Rooster, and you do nothing. Watch the cut scene to get a nice, healthy check mark. Easy!

- On to the real stuff. After a lengthy cut scene where the ‘heroes’ prove that they’re rather dickish, you’ll be dropped in the boots of an Old Lady. She’s quite weak at this point, and you should avoid fighting for the moment unless you’re willing to call in the cavalry. (Yes, despite the awful attitudes of the heroes, you still get Hero Call here.)

- You now have free rein over the Abandoned Village, though you can’t enter the majority of the houses and you can’t leave. Your options are basically limited to the Old Lady’s house. Before heading indoors, though, look around. There are several gleaming, tree-like tentacles here which you can fight. These are Infectious Goos, and they will kick the Old Lady’s ass if she fights it without a Hero Call. If you want to avoid losing points at the end of the chapter, avoid the tentacles.

- Pop into the Old Lady’s house. (It’s the one with the shining Jewelweed out front.) You’ll find three Herbal Dusts in a dresser here, and there’s a bed where you can sleep and restore your health. You can only use this bed twice, however, so save it for moments of dire need. To the right of the Old Lady’s fireplace is a hidden passage.

The rails in OH! RPG!'s Tunnels.
Wherever might they lead...?
The Tunnels

- The first thing to note down here is the purple liquid on the ground. Unlike topside, where you just couldn’t walk on the stuff, you can very easily blunder into it down here. It will sap your health at a distressing rate. This wouldn’t be such a big deal in other RPGs, but your healing opportunities are limited in OH! RPG!, so don’t take it lightly. It can kill you if you run out of health! You can use Herbal Dust in the same manner as Gobby Potions from the first chapter, amplified by Jewelweed, to restore lost health.

- The Tunnels branch out in maze-like fashion. Start by taking a left past the first, unavoidable patch of purple ooze, and keep to the left, heading north. The Old Lady will comment on a set of rails leading into the wall. Walk into said wall and stumble your way to the southwest - this will take a bit of doing, but you’re completely safe along the way - and you can find a small, ooze-infested basement with a gleaming stone tablet. Climb into the house above and you’ll find Algae String in the dresser and Serpent Boots in the chest. Equip these Boots immediately, as they ward off much of the damage you’ll take from walking over poison patches. The Algae String can increase their defensive score, as well.

- Head back to the visible portion of the Tunnels and continue northwest. There are two patches of Jewelweed along the way, and at the end of the trek you’ll find a ladder into another house. You’ll find an equippable Pipe sitting on the table beside the rails. It’s a bit stronger than the Old Lady’s current Sling, though she’ll be slower for it.

- Back into the Tunnels. To the right of this ladder are more rails, and they’ll take you to a lengthy, semi-visible passage flooded with ooze. Your Serpent Boots will allow you to cross without too much damage. A chest in the house above contains a Key. If you head back downstairs and backtrack one chamber you can go through the southern wall and loop east and north to get at the treasure chest near the ladder; inside is the Rifle the Old Lady mentioned before.

The Abandoned Village of OH! RPG!.
You've almost escaped...
Side Quest - Cleanse the Goo

Return to the surface and try to fight the Infectious Goos. They’re still strong, but if you equip the Pipe you will do a lot more damage with each stroke. Even better, the Old Lady can use the Head Bash skill to inflict tons of damage (1,000+!) and stun the Goo, preventing them from hurting you for a turn. Nice. Infectious Goos drop Cursed Roots, which can upgrade attack damage on weapons. You can fight four Goos: three in the town, and one outside the shack where you picked up the Serpent Boots. Killing all four completes the quest.

- Return to the entrance of the Tunnels and head east. You’ll find stairs into a house. Check behind the nearest stack of crates for two Antidotes, then, if you want some experience, head north after equipping the Rifle. A pair of Dark Rats will engage you in battle, and you can easily wipe them out with Grandma’s Gundust, learned by equipping the Rifle. This is a dead end, sadly, and you’ll be forced to head back into the Tunnels.

- Take a left at the entrance, then go north and east. There’s more ooze ahead, and a Bloodworm may come charging at you if you get too close. The Rifle can easily take it down; if you have something else equipped, beware its leeching attacks. You may get a Mythical Cornea and / or a Bloodsack for winning. There’s a Jewelweed attached to the wall, and if you carry on southeast, through a great deal of poison and past another Bloodworm, you’ll find more Jewelweed - and another house. A cut scene waits inside, as well as a chest containing Heavy Chainmail and cupboards with some Algae String, near the rear door and by the bed.

- Take the ladder just before you entered the long path to the previous house. It leads into another house - nothing inside, alas - and, beyond that, another section of the Tunnels. There’s a Bloodworm ahead, ripe for Rifling, and past that is a ladder into the house where you (may have) fought the Rats. Continue east past here to find some more Jewelweed before entering the house.

- Assuming you picked up the Key earlier, you can use it to unlock the back door of this home. On the cliffs out here you can from the entrance to a new area, the Secret Tunnel.

- You’ll face a Bloodworm a short trek into this branch of the Tunnels, and beyond it twin chests containing three Herbal Dusts and a Vermillion Dress. The Dress doesn’t provide as much overall protection as the Chainmail, but it adds to your water and poison resistance. Put it on. Just beyond these chests is a cluster of three Bloodworms; I highly recommend using Grandma’s Gundust to wipe them out in a hurry. Past them is an exit.

The Swamps

- After a quick trek to the east the path through this area branches to the west and the north. If you head west you can find a Mythical Cornea off to the side of the path, and at the end is a chest containing 500 G. Go north, which is kinda forced on you, and you’ll soon run into a brutal monster.

The Parasight in OH! RPG!.
It's not near as tough as it looks. It is as ugly, however.
Parasight

Remember that Vermillion Dress you picked up earlier? This battle is more or less why you should be wearing it now. Parasight is a powerful foe for the Old Lady, and aside from a normal, physical attack it can use Tainted Water, a watery magical attack, and Poison, which has a chance of poisoning the ol’ girl. The Dress will reduce the damage most of Parasight’s attacks, making the battle much easier. Two routes to win:
  • Surprisingly, the easier route is to fight on your own. So long as you have the Dress equipped Parasight won’t do that much damage. Throw up Herbal Remedy (learned at level 41) to offset the beast’s attacks for a few rounds, then pound it with Rifle blasts. It should go down after six or seven shots.
  • If you decide to Hero Call you’ll have the Inferno spell at your disposal. It’s more than enough to toast the Parasight in one hit, but it takes twelve freaking rounds to go off. Yeesh. This is one of the few cases where Hero Call makes the battle harder. If you really want Marsha to show up, defend your way through the battle and throw up Herbal Remedy a few times to heal. 
You’ll gain a Wormskin, and possibly a Bloodsack, for defeating Parasight. Wormskin is an excellent armour upgrade for your magic defence.

- Head north to find another screen. If you continue north you’ll see a chest ahead, though trying to get it will put you in a battle with another Parasight. You can skirt to the west to avoid the battle, though you’ll miss the chest, which contains 300 G. To the east is an undefended chest containing a Bloodsack.

- Far to the north is the Hidden Cottage. You’ll catch a cut scene inside, and then get forced into tunnels beneath the Cottage. Dash to the east. You can find 50 G by checking the cupboards along the way, but that paltry amount really isn’t worth dying for, since you only have fifteen seconds to escape. Then, when you hit the end of the line…

The Swamp Demon of OH! RPG!.
That's... that's just nasty, right there.
Swamp Demon

Hoo boy. That’s a big one, right there. The Swamp Demon vacillates between physical attacks - two per turn, sadly - and dark magic, including blasts of ice magic that reduce your stats and attempts to poison your characters. Yes, characters, plural, because Old Lady has Sunshine here to back her up for the fight. This seems good, but Sunshine can’t die during the battle. If she does, the fight ends immediately. The Swamp Demon has an ungodly amount of health, as well, so you’ll spend a loooong time keeping Sunshine safe. Your options:
  • You’ll have a fairly easy time of this battle if you decide to call in Marsha. Inferno only takes eight turns in this battle, and she mops the floor with the creature. Heal and smack the thing until it roars, then call in Marsha to finish the job. Heal as necessary. Sunshine can help the Old Lady in this regard, either through items or her own Healing Hands spell.
  • The fight turns into one of attrition if you decide not to call in Marsha. The Swamp Demon has 25,000 HP to start, and your attacks don’t do a hell of a lot of damage, even with the Rifle equipped. The secret here is to use the Old Lady’s Herbal Remedy spell judiciously. It costs next to no MP to cast (the TP cost kinda sucks, but your TP will build quickly), and will easily keep both characters out of the danger zone. Use items as needed, but they shouldn’t be needed too often. After a few minutes of attacking the Swamp Demon will rely strictly on its physical attack, at which point the remainder of the battle is a breeze - or at least it is until the Swamp Demon hit 3,000 HP, at which point there’s a good chance it will use X-Ice Blades, killing both characters immediately. This is completely random, and the only way to survive (on your first try, anyway) is to pray and have the Old Lady use Grandma’s Gundust as often as she can.
In other words, yeah, you will almost certainly have to call in Marsha to defend yourself the first time you beat the Swamp Demon. Well done on you if you can trash it otherwise! It is nevertheless wise to note that the Swamp Demon can use X-Ice Blades at the beginning of the fight, and so you should smack it around until it roars. Then you're free to bring Marsha along to wipe it out.

Part Three: Volcanic Mountain