The best way I can describe this book is, "This is 8-Bit B/X."
And I mean that in the most positive, excited, and incredible way. Those wonderful years of 8-Bit game consoles, and especially the NES - those are really cool memories. How they created new and cool experiences within the limited capabilities of that hardware and system and wowed us with the depth and creativity they had to squeeze out every drop of power and gameplay depth is a part of my childhood.
More with less.
You don't need 16 bits of CPU or power, and in fact, having more is a distraction that leads you down a path of disappointment. Because the door is opened to distractions, like the SNES's limited 3d, sprite handling, and the chase for lifelike graphics. We need more storage space for music and graphics! We need full motion videos! We need music streamed from the CD-ROM! Now we need 32-bit consoles...64 bit...more 3d hardware...CD ROMs...DVDs...Blurays...hard drives...SSDs...faster load times...AI acceleration...sound engines...game streaming...
When you go down that road you lose something. You lose the simplicity. You lose the core experience of gaming. By keeping the game simple and focused on a core experience, you free up the imaginations of players and game masters alike.
Monsters and Spells are Highlights
The monsters are really well done. I have not seen monsters this well done in a long time in pen-and-paper games. Each monster has a condensed list of notes, special attacks, defenses, or special rules following the description. The special attacks and defenses leverage the saving throw system. Sometimes there are treasure notes, surprise chances, who the monsters dislike, and other bits of useful information in these bulleted lists of notes.
I am reminded of the HARP monsters book and how a medusa's special abilities take up paragraphs of rules and information in the monster description. Here, a couple bullet points on how a medusa's attacks and special rules work, and we are on our way. Every monster is like that, just the rules for what we need to make it work, and do not belabor or drag out the information.
Spells are similarly cleaned up and organized and are just as much as a highlight in the system. Clean, concise, and unambiguous spells are easier to use at the table because there are no questions on their use and referees can rule consistently at every game table. Any special circumstances where referee rules are needed are out of the norm and not due to spells being written ambiguously.
Again, that 8-bit design mentality shines. Boil the monster down into exactly what we need to play it, make it work, make it clear, and make it a threat in the game.
The Art is Glorious
The art is generous, with two-page panel spreads throughout, and original, a wide variety of styles, and just wonderful. You know those incredible instruction manuals in those 8-Bit games of yesterday, often with anime or other dramatic art and lots of wonderful illustrations to get your imagination going? This reminds me of those fun little booklets that take a simple concept, a game where you have to use your imagination, and it seeds those ideas in your head. The art is perfect, and it is a wonderful example of letting the game master and players imaginations take it from there.
You want to run a game more lighthearted? The art supports that feeling. You want realistic and serious? The art is there to get you started. Silly and dungeon-trope humor filled? The art has that feeling covered as well.
The art meets or beats the quality of what is coming out of the big fantasy gaming publishers, and shows a remarkable diversity of style and theme that I find refreshing. Since the game will be many things to many people, the art should not look "all the same" and this goes wild and shows an incredible range of styles and themes that just makes the book a pleasure to open and flip through.
The equipment list is a little short, as it focuses on essential items, but this can serve to reduce the chaff and unimportant pieces of junk players are forced to keep track of. The individual weight of equipment items seems like an omission, because it is not on the list, but later on in the rules it is assumed each of these items weights 80 coins, so equipment encumbrance is covered, though in a simplified way.
Magic User spells go up to 6th level, and cleric to 5th. For those of us used to having spell lists that go all the way to 9th and 7th this may seem like a limitation, but I am find with it since the spells and the levels given are the ones that have seen the most use at our tables. Not every world needs those super high level spells, and there is a point where some of them got repetitive just higher powered. One could always port in those spells from other OSR products too, if you really, really want them.
Compared to the wonderful everything in there junk drawer of Labyrinth Lord, yes, this game is simpler and smaller in scope in regards to choices, spells, monsters, classes, and selection. However, there are times when as a group of players and a world builder - I want a smaller focus. A more focused starting point. A simpler framework from which to start from.
Labyrinth Lord can feel like a gigantic central subway station with crowds of people, bad guys, things going on, noise, and bustle and that can be a distraction to a group just trying to share a story that is focused on one conflict.
Let's say we have a story where an evil Baron is using a tribe of hill trolls to control a marsh community. In OS Essentials, we can focus on just that conflict easily. There is less chaff and distraction. In Labyrinth Lord, the sandbox of demons, undead, beings from beyond, hundreds of classes, thousands of spells, and all sorts of other distractions can take the focus away from that simple story very easily.
If you like modding Skyrim with 500 mods to have it all, including small scale wars between twenty factions, dragons, and the undead? Labyrinth Lord is your game. If you prefer a classic and simple tale of adventure like Zelda, where you need to figure out solutions given a limited scope and set of rules? OS Essentials would likely appeal to you more (though yes, you can just expand OS Essentials anyways with all the LL stuff and go wild, but Link will be climbing over piles of dead monsters and soldiers).
Both can exist together. Both have a different feel and focus. Both can be played and enjoyed by the same group. OS Essentials is more of a starting point for a game you take your way, than it is an already filled out sandbox full of classic game pieces.
There is a freedom in starting simple. Looking forward to diving into this one, and more soon.