Advanced Dungeons & Dragons 1st Edition vs Old-School Essentials

Compare Advanced Dungeons & Dragons 1st Edition and Old-School Essentials side by side. See differences in complexity, dice, genre, and more.

	Advanced Dungeons & Dragons 1st Edition	Old-School Essentials
Genre	Fantasy	Fantasy
Tags	Classic Fantasy, Crunchy, Descending AC, Dungeon Crawl, Inventory Management, Random Tables, Resource Management, Strong GM Support, Tactical, Vancian Casting	Dungeon Crawl, Exploration, Hexcrawl, Deadly, Sandbox, Resource Management, Inventory Management, Random Tables, Vancian Casting, Strong GM Support
Core Mechanic	Attack rolls use a d20 against class-and-level matrices to hit descending Armor Class. Other actions follow distinct procedures rather than a universal check.	Attacks roll d20 against an attack matrix or an optional ascending Armour Class target. Saving throws meet a category target on d20. Ability checks roll at or below an ability score on d20.
Dice	d20	d20
Complexity	Very High	Low
Availability	Paid	Free core rules
Runnability	4 of 5 book tools	5 of 5 book tools
License	All Rights Reserved	OGL 1.0a
Third-Party Publishing	No verified route found	Commercial publishing allowed — Open license
Summary only, not legal advice. Check current terms before publishing.
Publisher	TSR Games	Necrotic Gnome
Year	1977	2019
Languages	English, French, German	English, Italian, Spanish, French, Czech, Portuguese, Chinese, Korean
Best For	Groups who want a referee-built fantasy campaign driven by treasure expeditions and careful resource planning.	Groups who want treasure-driven dungeon expeditions and open wilderness campaigns with fragile starting characters.
Highlights	Recovered treasure earns experience, rewarding successful expeditions back to a safe base. Prepared spells make choosing tomorrow’s magic part of expedition planning. Dungeon generators let the referee create unexplored passages during play.	Treasure recovered from adventures provides most experience points, rewarding successful exploration over fighting alone. Reaction and optional morale rolls let encounters lead to negotiation or flight instead of automatic combat. Stronghold construction and taxation let accumulated wealth support a growing domain.
Considerations	Racial limits restrict which classes and advancement paths a character can choose. Successful hits interrupt casting and expend the spell. Failed saves against many monster attacks can kill characters outright.	Characters die at zero hit points, and failed poison saves are usually fatal. Demihuman characters combine ancestry with class and have lower level limits than human classes. Declared spells are lost if the caster is hit or fails a saving throw before acting.