A route in UNDERDEEP is a path you build out of map markers: you assign a behaviour policy to each tile, and during auto-play your character does whatever the policy on the tile it is standing on says. The Underdeep route settings in the in-game Manual document that whole policy list, and the setup below turns it into a route your character can walk unattended.
Underdeep route settings: the policy letters and what they do
| Marker | Policy |
|---|---|
| A | Go North |
| B | Go South |
| C | Go West |
| D | Go East |
| E | Use Potion |
| F | Do Evil |
| G | Do good |
The four movement directions are what auto-explore is scripted with - the direction buttons under the map are the A, B, C and D controls - and E, F and G add an action to the same tile. F and G are the policies that steer your karma: a tile marked F makes your character do something evil as it passes, and G makes it do something good.
Where markers go on the map
Markers are placed on individual tiles of the dungeon grid, which is addressed by X,Y coordinates starting at 0,0. The map itself fills in by itself as you walk, and coverage is what raises your run budgets - the cartography guide covers both, along with why coordinates are worth sharing.
Setting up a route, step by step
- Decide what the route is for. The developers name three archetypes: routes focused on uncovering unexplored tiles, routes that prioritise efficient character growth, and high-risk treasure-hunting routes that ignore danger.
- Place the movement policies along the path, one letter per tile, in the order your character should walk it.
- Put E on the tile you leave after a boss fight, so the character drinks a potion between fights instead of during one.
- Add the repeat key I next to any policy that has to fire more than once - this is how you keep retrying a door that failed to unlock.
- Give a tile a second letter where you need a fallback, so a used policy does not strand the character.
- Let the run start and watch the Moves, Fights and Loots counters in the run summary to see whether the route is worth repeating.
Once the route is right, how many times you can walk it in a day is decided by your loop tickets - the loop ticket guide has the daily numbers.
Why a policy only fires once
A single letter is spent the first time it fires. If your character steps on a tile marked A (Go North) and comes back to that tile later in the same run, the A counts as used and no longer triggers. To make a policy fire on every visit, pair it with the repeat key I: putting AI on a tile re-activates the A whenever you leave the tile and step on it again.
Two policies on one tile
A tile can carry two different letters, and the character then has a fallback sequence. If C has already been used, for example, it goes B south and then C west to reach the goblin mage, then D east to the two goblins. This is the standard way to write a route that must survive a door it failed to open on an earlier run.