Bounded Accuracy is Fragile

I picked up the monstrous Tales of Arcana 5E Race Guide, and this is a unique and fun book that gives you hundreds of 5E races to play with. Some are silly, and I would not use them as-is, but this book is unparalleled as a font of imagination and creativity. Many of them are handy and inspire me to use them as characters or NPCs. I like this book as a "default race guide" for a D&D 4E-style of a world where anything goes.

All of them are skinnable and hackable, so if you wanted a race of winged beast-men you could base them on a satyr, drop one of those abilities and give them wings (which start at gliding, can level up with feats). So the choices here are infinite, given a bit of creativity and imagination. Robotic demons? A race of intelligent mice? Cloud people? A jelly slime? Pick something close and start swapping abilities. This book is excellent for sci-fi too.

When I started to use them in 5E, I noticed they were slightly overpowered. Just barely enough to make them stand out from the default race selections. Then I noticed how just a few ability score points here or there, and a couple critical special abilities easily break 5E.

If I used this as my book for a campaign, it would be an all-or-nothing book for that game. Everyone picks from here, or no one does. Use these versions of elf, human, and dwarf, please, since they are more balanced than the default 5E versions. The default picks are more powerful than the choices with most 5E games. I see why you must make things fair when comparing them to other choices in this book.

I had to take a step back. B/X did not break this easily. Even in AD&D, the game handled that fine when I had a character who rolled three 18-ability scores. Thanks to bounded accuracy, 5E is tuned so tightly that it breaks when you give a character a few extra ability score points. Most modern tabletop games are like that, including Pathfinder 2.

Give one character a +2 STR and cold immunity because he is a yeti, and the game goes to hell. Other players get jealous. The rules break. Sick damage is being done. The Yeti WWE body slams a white dragon. It is fun for a few sessions, but the piling-on becomes apparent as you level. 5E was just not designed to handle this.

With many expansion books, you accept the broken nature and hope everything balances out. With enough broken content, everything is balanced, right? It is funny since things that would not break other games do in 5E. Giving up on balance is a game balance strategy in 5E.

And then, for fun, I used these races as-is to create Castles & Crusades characters. Most abilities can be written down and used as-is, and ability score bonuses fit right in. I had a few ground rules:

• If a race gives proficiency in a 5E skill, it gives a flat +2 bonus to those activities in C&C. Acrobatics skill would be a flat +2 to acrobatics checks.
• Bonus actions are not supported; those abilities must be used as an attack action.
• If a race gave a cantrip ability, that could be used once per day per level.
• Tool proficiencies grant a +2 at actions used with that tool.
• Instead of granting advantage, give a +3 to that roll. A disadvantage is a -3.
• Wings need the optional Advantage system (CK Guide) to be used to upgrade them instead of feats or just auto-upgrade them every 3-4 levels.
• Spell damage from 5E should be halved as a general rule. If scaling is mentioned, add a die damage per 2 levels, starting at 3rd, like magic missile. Any 5E spell converts this way.
• For "feats," use the Advantage system out of the CK. Humans start with two.

A few minor tweaks here and there, and all of these races can be used with C&C or any B/X version of the game. And the ability score modifiers do not break the game. They have a giant race that raises STR by four, and in C&C, even if I did a 4d6 and dropped the lowest, that would be a 16-18 STR on average or 20-22 (+4 or +5) at worst.

That +5 modifier is not a big deal in C&C, where a level 10 fighter gets a +10 base to hit. It is a good modifier, but it is not breaking the math. In Old School Essentials, that modifier is even better, but it likely won't break the math there, either.

The game handles it. All B/X and 3.5 games before D&D 4 handle this easily, and the character may be a little powerful, but they don't break the game at level one or twenty. Castles & Crusades eats these races up; sure, you have a host of resistances, a cantrip per day ability, and can glide with wings, but you only have 8 hit points at level one and an AC of 11-15.

Like 5E, if I were using this book for C&C, all races would come from this book, or none would.

Castles & Crusades is not hard to hack into a rules-stable, retro 2.5E version of 5E. It feels like B/X, yet it has a 5E flavor. The gameplay is high-speed without too many rules, and legacy cruft slows down a combat round. The action economy is simple, one action (attacks allow a half-move). C&C is built as a hacker's game, and you can do a lot with it, even emulate 5E pretty nicely.