B/X Mars Wilderness Encounter Table

 [EDIT/UPDATE] A slightly more polished PDF is available for download now, formatted to make the table useful at the table.

Michael Gibbons goes by the name Aos online and hosts the Metal Earth blog which is filled with gamma-radiated world building. His illustrations are uniquely his own, I commissioned two pieces for DUSRS&S so I like his thick black and white illos. He also released his own comic book, so yeah, another middle-aged ttrpg enthusiast like myself who creates cool shit for their games and also posts them online! If you like Lyn Carter’s spin on the science-fantasy genre you are going to love Metal Earth’s maps and site locations. 

He recently released a collection of these creations in a hardback book dubbed B/X Mars. The title immediately clues you in this is another entry in the thick DIY file which is the OSR. And that it is a setting book. Called Mars. So you are in the world of John Carter here, red sands, swords and laser beams, aliens, etc. This is Appendix N stuff. There are 95 pages of content and loaded with Michael’s great drawings. There is a brief, coherent introduction to the Mars of the past and the all-important present followed by character creation. They are Princess, Warrior, Terran, Thark! (always spelled this way), and Menton. Solid John Carter of Mars stuff. Mind Warp is your “magic” system and is the province of Mentons and fields of “mastery” replace skills. Saving throws have their own titles so one is left to assign them as they see fit if you want to compare them to standard OSR saving throw titles. This is how I broke them down; Death Ray/Poison, Warp/Spells, Entangle/Breath Weapon, Fear/Petrify, Rods and Crown is Wands obviously. Desert gear, weapons of the wasteland, airships, weather, these are the first 22 pages.

Layout is simple two-column with a 12/14 size font and bolded section titles, making it an easy read. There is a generous amount of white space (the book is 11 x 8.5) and I, for one, like this in my game books because I write on them. The way POD page count falls you end up with 5 blank page faces at the back. I could run a campaign with all my notes and prep written in the book with this kind of writing space. I think this is the only setting book I’ve picked up which has offered up this amount of white space. I don’t think this is overly intentional. I think Gibbons is like myself, an ametaur layout guy so each book looks loose. 

Part three and part four of the book is your gazetteer. Like McKinney’s Carcosa setting book, B/X Mars is content to give a detailed description of only a small section of the world. In this case it is a land on Mars referred to as “Zerzura”. The map of Zerzura is a good example of an “evocative” map. The hand-drawn cartography and unique place names do what the best ttrpg maps do, spark adventure ideas! Gibbons has several area maps on his blog you could use for whole campaign maps, all of them he draws spark adventure ideas just looking at them. A bestiary of unique monsters to the setting and a couple of detailed site locations finishes the book up, and like I said earlier, plenty of content you could run your 1st edition Gamma World campaign for years just building off the stuff in B/X Mars.

What it doesn’t have is charts. Specifically random encounter charts. Look, I know, creating tables with your publishing software can be a whole hell of a pain in the ass. Being able to type away endlessly and shape that up into readable content is easy. You will get your book done a whole lot faster if you skip tables, I get it. But OSR begs for random encounter tables. This harkens back to the game’s roots where the next exciting adventure is unknown till encountered by a chance roll of the dice. And is a big omission for an old-school setting book. I am going to correct this by creating random encounter tables for the game and post them below, free, for the world to use. Now, grab hold fast the line and swing from your armed airship into fantasy last-planet adventure with B/X Mars!

Roll 1d100	Wastelands	Desert	Ruins, Subterranean	Mountains	Forest	Swamp
NPC Character	1	1	1 - 5	1	1 - 2	1
Desert Gear	2	2 - 3	6		3
Weather Event	3 - 5	4 - 6		2 - 12	5	2 - 5
Random Faction	6	7 - 8	7 - 10	13	9	6
Thoat	7 - 10	9 - 15	11 - 12	14 - 16	18	10
Banth	11 - 12	16 - 18	13 - 18	17 - 24	24	16
Albino Ape	13	19 - 20	19 - 22	25 - 30	28	20
Crimson Ape	14	21 - 22	23 - 24	31 - 38	32	26
Sllarg	15 - 18	23	25	39 - 40	33
Skraayth	19 - 23	24 - 26	26	41 - 43	35	30
Sand Creep	24 - 25	27		44	36
Kraux	26 - 28	28 - 30	27 - 30	45 - 50	40	34
Nuerowolf	29	31 - 35	31 - 36	51 - 52	46
Siren Spider	30 - 32	36 - 38	37- 40	53 - 55	50	40
Grune	33 - 35	39 - 40	41- 42
Slaves	36	41	43	56 - 58	55	41
Grakkon	37 - 40	42 - 45	44 - 48	59 - 60	57
Tripod	41	46	49 - 52	61	58	42
Martian Dragon	42	47	53	62	60	43
Giant Roc*	43 - 45	48 - 50		63 - 65		48
Near Cat	46 - 49	51 - 53	54	66 - 67	65	52
Leviathan	50 - 52	54 - 56		68 - 70	68	55
Shoum	53 - 55	57 - 60	55 - 60	71 - 72	69
Archeoptron	56	61 - 62		73 - 75	72	58
Jade Wasp	57 - 59	63	61	76 - 77	75	63
Reptoid	60 - 62	64 - 65	62 - 65	78	78	70
Azure Martian	63	66	66 - 68			71
Bone Angel			69 - 73	79 - 80	79	75
Ghost Fish	64 - 66	67 - 72	74 - 75
Dragonoid	67	73	76 - 77	81 - 83	82	80
Dust Devil	68 - 70	74 - 75
Monnx	71 - 72	76		84 - 85
Giant Mummy	73 - 75	77 - 80	78 - 80	86	85	81
Deathspore	76 - 77	81 - 82	81 - 83		87	86
Spore Zombie	78 - 79	83 - 84	84 - 86		89	89
Sky Devil	80 - 85	85 - 92	88	87 - 90	93	90
Stichling	86 - 88	93	90		95	94
Moon Apes	89 - 90	94	94	91 - 94	96	95
Airship	91	95	95	95 - 96	97	96
Vat Goon	92 - 95	96 - 98	98
Kryss	96 - 98	99	99	97 - 98	99	98
Kryss Drone	100	100	100	99 - 100	100	99 - 100