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Sci-fi RPG Substratum Protocol channels the “deep delving mystery” of Subnautica and In Other Waters

Pandion’s latest title supports both subterranean solo play and group delving.

Art from tabletop RPG Substratum Protocol
Image credit: Galen Pejeau/Pandion Games

Discover a hidden universe of mysteries during a scientific expedition to the Earth’s core in Substratum Protocol, a new tabletop RPG that focuses roleplay on three core pillars: descend, learn, survive. This hard science fiction title about subverting an apocalypse supports both solo and group play and recently launched a Backerkit campaign.

The design team at Pandion Games describe their newest RPG as an entry in the Deep Delving Mystery genre, joining atmospheric video games such as Subnautica and In Other Waters. Like those games, Substratum Protocol encourages players to amass knowledge about their surroundings in order to better navigate the alien ecology deep below the surface. Unnamed horrors lurk here and will need to be faced down or craftily avoided to gather clues and solve the mysteries facing humanity.

Substratum Protocol’s rules are based on the Breathless system designed by Fari RPGs and uses a combination of polyhedral dice and a deck of regular playing cards. Players will assign different dice ranging between d4 and d10 to their skill loadout during character creation. When acting under stress or risky situations, players choose two skills, draw two cards from the deck and then roll those skills’ dice. The combined result is compared to the card - beating it earns a success and grants them the card as a resource to be spent later.

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Once a skill has been used in a check it “steps down” in value, making over-reliance on a single strength pretty disadvantageous. Luckily, cards earned during contests offset this degradation by powering various abilities within each scientist’s exosuit. Some will allow them to heal or create items, while others grant level-ups or even more powerful abilities.

The core rulebook contains a bestiary of 20 creatures ranging from the curiously similar to truly alien that players might discover during their slow, gruelling descent. But the real reason for tunnelling further than humanity ever has before is to seek an answer - or as Substratum Protocol puts it, assemble the final hypothesis. The group will encounter and record clues during the length of the mission and must synthesise them into a plan to close, control or otherwise neutralise the reality rending portal threatening all life on earth. The last phase of the game is all about this final hypothesis and learning whether or not these scientists learned enough to save humanity.

Ultimately designed to handle a collaborative group of scientists, Substratum Protocol will ship with special rules that handle two different modes of solo tabletop RPG play. The Hints and Hijinx system at the beating heart of this game was initially designed with solo play in mind, according to the designers. So, returning to that style simplifies the flow of play but loses out on the complexity of multiplayer. That’s why the designers included tools for achieving multi-scientist stories even when the group’s human contribution is a single player.

Art from tabletop RPG Substratum Protocol
Image credit: Galen Pejeau/Pandion Games

Pandion Games’ Andy Boyd is joined on the design team by editor Eric Lazure, illustrator Galen Pejeau, layout director Tony Tran and developmental editor René-Pier Deshaies-Gélinas. A free preview PDF provides a clear look at the direction these folks have taken the game, including some delicious retro-future graphic design and secondary footnotes, asides and commentary from an unknown reader whose comments deliver flavour and worldbuilding.

Substratum Protocol’s Backerkit campaign will run through April 25th and is crowdfunding both a physical and digital PDF version of the game, which the publisher expects to ship by June of this year - an ambitious goal but one Pandion Games seems confident in nailing.

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