Core Mechanics of Lighthouse at the Threshold

Fiction First

Lighthouse on the Threshold is a game about two things. First, creating an immersive world for players to explore and interact with, and second, challenging players to use their own wit and skill to overcome challenges presented to the from the world. Both of these objectives can be accomplished without players understanding anything about how the mechanics of this game actually work. This is why, when you play or run this game, you should first make sure players understand the fiction that surrounds their characters, and the puzzles that they face. The mechanics of the game are used for only one small portion of the actual game-play, and if they ever get in the way of the fiction, they should be ignored.

Core Game Loop

The core game loop of Lighthouse on the Threshold is this:
1. The GM describes the scene.
2. Players ask questions and make decisions
3. The GM determines what happens.
4. Repeat.

This, in its simplest form, is what you and your friends will be doing at the table. The players and the GM having a conversation about what is happening in the fiction of the game. When you are unsure what to do next in the game, refer back to these steps.

1. The GM describes the Scene

The adventures in this book or the GM’s imagination will take care of step one. The GM should either find or prepare a rich, detailed adventure with a world, situations, and characters that the characters can explore and interact with. Your job as the GM will be to convey each scene to the players in evocative detail. It’s not easy, and there is a lot of nuance to it. Don’t worry though, you can do it, and I’m going to help you do it!

2. Players ask questions and make decisions

Next players ask questions and decide their next course of action. Players who ask good questions and make good decisions will excel at this game. Players who rush into situations without having conversations with the game master will lead their characters to an early end. Lighthouse on the Threshold has an ending; a solution, but it will only be reached through expert role-playing; and expert role players ask great questions and make good decisions.

Game play and the GM’s decisions should always be laser focused on the quality of the players questions and decisions. If the players ask precise probing questions, the DM should answer with truthful information whenever possible. When the players make good decisions they should be rewarded with success in their plans. The whims of fate (dice rolls) only apply to players who haven’t created a fool-proof plan.

3. The GM determines what happens.

The mechanical rules of the game are mainly concerned with the 3rd step, determining what happens, but most of the time, you shouldn’t need to refer to the rules. The GM should always try to determine what logically follows from the players actions to determine what happens. Only when the GM determines that outcome of some course of action is uncertain, do you need to refer to the rules to simulate an outcome.

The core game mechanics listed below are the main ways to determine uncertain outcomes.

Skill Rolls

Normal: 2d6 + Ability Modifier
Advantage: 3d6 keep 2 + Ability Modifier

When a player is attempting anything and the outcome is uncertain, you can ask for a skill roll. First determine which Ability score is applicable (Body, Awareness, or Ego), then the player rolls 2d6 and add’s that ability score modifier.

Use the body score to determine physical skill checks; awareness for skill checks that rely on reflexes or perception. and ego for checks that require intelligence or charisma.

Players can gain advantage on a skill roll in 3 ways.
1. Spend one ability point of the ability associated with the check.
2. If the player has a skill that is applicable to the situation, they gain advantage on the check.
3. If the player is in a situation where they would logically have an overwhelming advantage.

Skill rolls are always compared against the following chart.

Roll	Outcome
1-6	Failure & Complication.
7-9	Mixed
10+	Success

Failure & Complications
If the player fails, the player does not accomplish what he set out to do, often times with terrible consequences that follow on. DM’s are encouraged to come up with complications that follow from failure. Character harm, losing resources, complicating another characters turn are all valid choices. Never add complications that don’t follow logically from the players action or the situation.


Success
If the player succeeds, the player accomplishes what he set out to do, and may even have other benefits that logically follow on from his success. Conserving resources, setting up an ally for success, and more.


Mixed
A mixed result can have a variety of outcomes, all of which should flow naturally from the fiction of the game. The DM will choose a result that makes sense considering what the player is attempting, and what the context is.

1. The player succeeds at their task, but with some cost. The cost must always make sense according to what the player has actually done.  Some examples include…
* An item is destroyed or degraded.
* The character is injured.
* An opponnet gains an advantage.
* The character loses ego, awareness, or body points.
2. Partial success. The player only accomplishes part of what they were attempting. This result should only be used if a partial result will help the player along in their goals, but also provide a logical, yet entertaining complication.
3. Failure, with a twist! The player doesn’t accomplish what they were attempting, but succeeds spectacularly at accomplishing something else unexepected. This result should be more rare, but sometimes the fiction of the situation will allow for it. Only use this if the players failure is a complication, but their unexpected result is a new opportunity the party can take advantage of.

Attack Rolls

Normal: 1d20 + Attack Bonus + Ability Modifier
Advantage: 2d20 keep 1 + Attack Bonus + Ability Modifier

Combat is inherently unpredictable, and so a roll is always called for when characters clash in deadly battles. Whenever you attack something in combat, you roll 1d20 and add your attack bonus and the relevant ability modifier, trying to meet or beat the Armor Class value of the target you are attacking.

Different kinds of attacks use different ability modifiers.

Melee attacks: Body Modifier
Ranged attacks: Awareness Modifier
Magic attacks: Ego Modifier

Attack bonuses are gained through training, magic items, completing quests, being blessed by a fairy queen, or many other things that can happen in the game.

Players can gain advantage on Attack rolls in 3 ways.

1. Spend one ability point of the ability associated with the check.
2. If the player has a special ability that grants him advantage.
3. If, in the fiction of the game, it makes logical sense that the player would have an advantage on his attack.

A Note on ‘Saving Throws’

Lighthouse at the Threshold doesn’t have traditional saving throws. In other old-school games, when the player makes a mistake, their character can sometimes be saved through the use of a saving throw. In LatT, saving throws are often a choice given to the player a choice that amounts to, how do you react to this threat? For example, when a armored knight walks into the path of a hidden flame jet trap. In other old school games, they would get a reflex save, or a save against breath weapons to mitigate this. In Lighthouse at the threshold, all the damage is rolled for the trap, and the player is given a choice. They can choose between expending their hit points, or their awareness points; awareness points representing using their reflexes to dodge out of the way.