Right about now, you are either saying "Oh yeah, I remember those!" or "What the hell is Castle Arcania? Wasn't that for SuperNES?" But it's one of my favorite pieces of gaming material, from a real oddity of a series, and oddly influential on me.
Back when I played one-on-one with my cousin (gaming had become uncool compared to Motley Crue and sports for my other players), I ran a wizard names Neves. Got him up to level 11 or 12, IIRC, and then we decided to just bump ourselves up to the high teens so we could try out the really cool high-level stuff. Yeah, yeah, GM PC, playing alongside, yadda yadda yadda. We had fun, my cousin with his two PCs (one a cleric, the other . . . I forget, a fighter I think) and me with Neves. I kept using Neves as an NPC in my later games, too.
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Castle Arcania is from the short-lived "1on1 Adventure Gamebooks" series, which also had some book about a robot and a space hero. It's kind of a mashup between Choose Your Own Adventure books, D&D, and a head-to-head boardgame.
There are two books - one each for Neves, "An Ancient and Powerful Wizard," and for Eric Sunsword, "Legendary Knight of the Northern Marches." Neves is a Neutral wizard, Eric is a Lawful Good fighter. The story is as follows - Neves wants to marry the beautiful princess Mara, so he can have eternal happiness (and eternal youth, all the better). Eric and Mara love each other, so you can see how this doesn't fit into their plans. So Neves busts into the castle, tosses some spells around, kidnaps her, and flees with his allies to the ruins of Castle Arcania, a handy castle-and-dungeon. Eric gives chase.
Low on spells after the big dustup at the castle, Neves's goal is to find enough magical items and allies in the dungeon to trash Eric in a heads-up fight, or get Eric killed by its inhabitants. Either way, with Eric out of the way he can Charm his princess and marry her. Yay, evil! (Er, neutral!) Eric's goal is to rescue her.
Both Neves and Eric have a posse of allies, each with their own special abilities, magic items, spells, and so on. Neves gets a gladiator bodyguard, a dark elf (not a drow), a female thief, and a kobold chief mercenary. Eric gets an amazon warrior and a reformed gentleman thief, each more powerful than any of Neves's allies. You can find more allies in the book (some monsters will fight you, others will join you if you play it correctly) and acquire more magic items. Some monsters will automatically ally with Neves and attack Eric, and vice-versa. In repeated play, you'll know which ones . . . so you can seek out allies or hunt down potential allies for your opponent. The whole time you need to avoid death at the hands of monsters, traps, and special encounters.
You play the game by alternating turns, reading an entry and following the text to know what to do - gain an ally, fight a monster, get a special result. You go back and forth, until eventually you end up face to face with your opponent and fight one another.
James M. Ward put in some nice touches. Eric's book tells you Castle Arcania was ruined in the past. Neves's book tells you that you helped trash Castle Arcania in the past. Heh. Some of your allies and your opponents allies have a nasty history, too, and preferentially attack each other even when you want them to all gang up on the name character. He also managed to make Eric Sunsword not-lame, which is tough for a LG goodie-goodie rescuing his chaste bride-to-be. He's tough and driven, and fun to play in his own right, and not just a foil for "I get to be a bad guy for once!" Neves.
How combat works is that the attacker (whoever goes first, and the text just tells you that) calls out a number 1-20, and the other player calls out one from 1-20, and you compare the results on a table. In actual play, you'd have enough combats that people would know which numbers you needed to make the other player's choice suck. So we almost immediately switched to using opposed D20 rolls, which made the game immediately more awesome. Anyway, you cross-reference numbers and get a result - hit, miss, double-damage hit, or a special result that depends on the character who gets that result. The specials can do cool stuff for you or bad stuff to you. Otherwise your weapons do a flat amount of damage, and monster attacks do the same, and you mark off HP as you take damage. You run the monsters when your opponent fights. When you eventually meet for the showdown, you just follow the same rules to kill each other head to head. They work fine in actual play both against monsters and PvP.
The game can get a little unbalanced, though. I distinctly remember playing one side (I think I was Neves), hoarding up a bunch of killed one-shot items, tracking down Eric, and wasting him in short order. Eric's player (my cousin) had suffered fairly badly in the dungeon and wasn't fully up to a fight and I was lavishly equipped. That was annoying, and I could understand my cousin's frustration with the results. Similarly, you can play Eric and load up. The game does reward you for holding onto the good stuff until the climactic battle, but then again so do most games.
So what can I do with these books?
You can play them straight up - which is wicked fun. Or you can steal the living hell out of Jim Ward's unique monsters, odd magic items, and fun traps. Some of these items are pretty bland ("wand of lightning bolts"), some are lame ("Heart Throb" is not a good name for a bow, sorry), and some are very cool indeed (I liked the mace "Armor Ruin" and its odd light-eating drawback), and just beg to be converted into your favorite game system and used. For D&D and retroclones, this is easy, because the books are basically D&D without slavish following of the rulebooks.
If you don't play a D&D clone . . . I've said this before, you better know how to convert from it or just steal ideas.
Content: 5 out of 5. A complete game in two little books. Replay value is pretty high, because fights can turn out differently, you can switch up the sides, you can easily modify the resolution system with dice, etc.
Presentation: 5 out of 5. Aside from a need to flip around to your character sheets, the books are very easy to use. The illustrations range from acceptable to excellent and always match the text. The books are easy to read and pretty durable, too.
Overall: These books are a lot of fun, and there seem to be some reasonably priced copies on Amazon.com and eBay. I'd play them again, anytime, and I thought they were very cleverly done. Plenty of (illustrated) monsters to steal, too! Check them out if you can! Recommended.