Combat-Free Subterranean Exploration
Mining in these parts can be dangerous. Yet we make sure our players stay in the safe boundaries, in any case of danger or hazard we encourage players to pay up and hire some professionals to deal with them.
Project Tallus Case Study
TALLUS MINING SYSTEM
a system design documentation
“My pickaxe is my lineage, I will extract every ore as long as I am needed” – Boney Dwarf Guy, to his mirror.
A technical systems design and architectural case study exploring deterministic procedural generation, mathematical depth scaling, and organic session loops for an infinite and intricate mine network.
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Mining Design Pillars
Atmospheric Tension
No-monsters doesn’t necessarily mean you can wander around freely, it is still very deep underground, did you pack your Sunstones? Whet your Pickaxe? Took out your socks from the back so you can have enough Inventory? Because these three have limits that will make players have to return to the workshop.
Cozy Player-Driven Pacing
We are working on preparing a mixtape for you as soon as we find the cassette player. Cause while you are sipping your coffee and swinging your pickaxe freely, you’re gonna enjoy breathing in the humid weather down here, we don’t rush you to explore, pick your own floor and explore at your own pace!
Chapter 01
Session Architecture
It’s fairly easy you know... You take your pickaxe, enter the mine, explore the mine until your ran out of light, durability or inventory space. Then whenever you feel like you coming back you just channel magically and teleport back to the workshop. Next time you enter you can use the activated elevators located at every 10th floor.
Challenge
The mining session needed pressure, without a countdown or combat. Players needed reasons to return to the workshop while still feeling that the decision to leave was theirs.
Approach
Built the session around limited resources rather than a fixed timer. The player enters from the workshop, explores and mines until their available limits make continued descent increasingly unattractive, then returns to base. Milestone elevators provide persistent shortcuts between sessions.
Outcome
Session length is shaped by player decisions and resource pressure rather than a forced countdown.
Core Session Loop
Lifecycle of a single session, governed by 3 organic player limits, where departure can be triggered at any time during the exploration phase.
Multiple dots do not indicate multiple sessions*
Workshop
Main location of the Crafting* system. Base of operations for Blacksmithing, where different refinement stations and storages are located and items are crafted. Backroom to the Shopkeeping* system. Players use the main descend shaft here to enter the mine or directly select a floor with an active elevator shaft.
Chapter 02
Infinite Strata
The floors inside the mine network are procedurally generated, the level you explore in earlier sessions will look different, on top of that, it goes deep... to infinity. Yes, infinity. The first 200 levels though are where the main action is and all the new content is there. We will not stop you from going deeper, you may want to challenge yourself but you’ll see those depths are not as efficient.
Challenge
A 200-floor mine needed to feel progressively diverse without requiring every floor to be manually authored. At the same time, depth must affect resources, environment and tool progression keeping the diversity.
Approach
Used depth profiles to continuously control environmental characteristics and resource availability, while milestone floors are kept authored and persistent as landmarks. L1–L200 contains the designed progression; further depths remain technically scalable beyond the authored boundary/
Outcome
Depth becomes a continuous system of environmental and economic change rather than a collection of isolated levels.
Subterranean Strata & Distribution Architecture
Level specific map of the mine network, each floor level has its own unique identity called profile that is used as a procedural generation guide.
Serpentine Descent Track Domain: L1 – L200 (Full Mine)
1 200
Floor Profile Details
Shallow Shafts
Familiar, safe, grounded baseline mining environment establishing core mechanics.
Topology:
Warm earthy tones, wooden beam supports, abandoned mine carts
Standard Shaft
Ladder & rope descent. Next checkpoint at L10.
Geological Distribution
Man-made Traces
100%
Rock Hardness
20%
Moisture Level
10%
Ambient Heat
0%
Mushroom Density
15%
Otherworldly Presence
0%
Available Resources
Telemetry Stream Carousel
•
Dataset 1 / 2
Geological Presence Curves
Variables
|
Continuous Cartesian Plot (X: L1–L200, Y: 0–100%)
Click / drag on graph to scrub active floor
Tool Tier Acquisition
Pickaxe Tier is not directly tied to the biome regions but have the intended most optimal depth bands. Necessary upgrade blueprints can be found in specified depth bands for each tier.
| Pickaxe Tier | Optimal Depth Band | Blueprint Drop Range |
|---|---|---|
| Tier 1 | L1 – L15 | Starting Equipment |
| Tier 2 | L16 – L39 | L10 – L15 |
| Tier 3 | L40 – L75 | L30 – L39 |
| Tier 4 | L76 – L141 | L65 – L75 |
| Tier 5 | L142 – L200 | L130 – L141 |
Chapter 03
The Playground
We made a little toy here so you can feel what it’s like to mine -though approximately- when you’re down there. Select the floor, the pickaxe you have, the resource you want to hit and it’ll show you what expects you. You can find the formulas inside the drawer.
Challenge
Deeper resources needed to become harder to extract without making mining progressively slower at every stage of the game. A stronger pickaxe also needs to feel meaningful without making earlier resources completely trivial.
Approach
Separated depth scaling and tool progression. Resource resistance increases with depth while matched-tier pickaxes compensate for that increase, targeting a relatively stable Time-to-Mine range. Tool condition further modifies performance without introducing a traditional break state. More variables to tweak meant more control on the scale.
Outcome
Depth increases extraction pressure while tool progression make sure efficiency stays similar, keeping mining relevant throughout the authored progression.
Mining Simulator & Scale Calculator
This interactive tool uses the approximate formulas used in the game with unbalanced versions. Instead of reading and looking at cryptic formulas, we provide the sensation of the mining we intended to achieve.
Input & Parameter Controls
Floor 1
L1 (Shallow Shafts) L40 (Subterranean Rivers) L76 (Magma & Thermal) L142 (Nethermost Region) L200 (Abyss)
1.0× Strike DMG
4 Available
* Grid dynamically filters native resources across L1–L200.
Stone Node
20 / 20 HP
Click to Strike Deposit
Tool Durability
600 / 600
Simulated Stats
Matched • 1.0× CheckTier 1 Tool vs Tier 1 Deposit • Matched Efficiency
Scaled Node HP
20
Floor-scaled base HP
Effective DMG / Hit
10
Wear & Tier adjusted
Hits Required
2
Discrete strikes to break
Time-to-Mine (TTM)
Matched
2.0s
Cadence: 1.00s / swing Target: 8.7s
Hardness
1.0
Durability tax / hit
Time to Impaired (TTGI)
1200s
1200 hits remaining
Formulas & Calculation Mechanics
1. Condition Modifiers
M_durability = 1.00 (Intact: Primary > 0)
M_durability = 0.50 (Critical: Primary = 0)
M_durability = 0.25 (Impaired: Depleted)
2. Floor-Depth Scaling
NodeHP(d) = BaseHP × (1.0 + 0.08 × (d − 1))
Linear 8% health expansion per floor
3. Tier Differential Check
M_tier = 1.0 (Tool Tier ≥ Node Tier)
M_tier = 0.5 (Tool Tier < Node Tier Penalty)
4. Damage / Hit Formula
Damage = max(0.25, BaseDamage × M_dur × M_tier)
Hits = ceil(NodeHP / Damage)
5. Time-To-Mine & Wear
T_swing = max(0.25s, 0.8s / HitSpeed)
TTM = Hits × T_swing
DurabilityTax = Hits × Hardness
6. TTGI & Milestone Loot
TTGI_hits = floor((Primary + Critical) / Hardness)
Drops @ 75%, 50%, 25%, 0% HP
Stage 4 absorbs remainder (Zero Loss)
* All formulas subject to balance tuning after actual playtests and does not reflect the final results. Reworks may and will happen regarding the approach and calculations of these formulas
Mining Time-To-Mine (TTM) Scaling Graph
The graph displays the efficiency of each pickaxe tier on any given floor. The painted area indicates target matched pacing band which is the intended TTM for each tier.
View Mode:
Active Floor: Floor 1
Native Domain: L1 – L15
Floor 1 P1
Exact TTM: 8.7s
P1:8.7s
P2:6.0s
P3:4.0s
P4:2.0s
P5:2.0s
Tier 1 Pickaxe Native: L1–15 • Max: 250s
Tier 2 Pickaxe Native: L16–39 • Max: 220s
Tier 3 Pickaxe Native: L40–75 • Max: 160s
Tier 4 Pickaxe Native: L76–141 • Max: 50s
Tier 5 Pickaxe Native: L142–200 • Max: 11s
* Curves will be subjected to balancing changed after the playtests
Pickaxe Durability Logic
The pickaxe never truly shatters and rendered disabled. However its durability faces degradation in two phases.
[Primary Pool]
Intact State
Primary Durability > 0. Standard throughput
[Secondary Pool]
Critical State
Triggered when Primary = 0. Capacity equals 100% of the Primary Pool, half of the original damage.
[Infinite Fallback]
Impaired State
Triggers when the Secondary Pool is depleted. Quarter of the original damage. Endless Pool.
* Pickaxe can be repaired both in the workshop and randomly encountered workbenches in the mine. Difference mainly being the cost
Chapter 04
Procedural Generation & Session Memory
This mine is endless, so it’s not possible to descend from the same shafts every time, therefore you see different layouts each time unless they’re kept in memory. Here, we’re explaining how that magic happens under the hood, each step we add a little detail for you each as important as the other. The end product? The same feel with a different map.
Challenge
The mine needed to generate different layouts across visits. Storing every generated floor in memory would scale poorly as the player descends. Also a method needed to make floors not repetitive so players can visit the same floor every session while finding complete different and fresh layouts.
Approach
Generate floors deterministically from their depth and generation identity. During a session, maintain a five-floor active memory window and reconstruct evicted floors from their deterministic identity if they’re revisited after the flush.
Outcome
Generated floors can be discarded from active memory and reconstructed later without feeling the same exact floor.
Generation Pipeline
The exact deterministic floor generation pipeline breakdown.
01 — Mine Seed
The mine is initialized with a global seed that provides the deterministic base for generation.
02 — Floor Depth
The target depth selects the floor's position within the mine and determines which depth profile applies.
03 — Depth Profile
The profile defines the environmental and procedural characteristics of the floor, including space, resources, hardness and environmental features.
04 — Floor Seed
The mine seed and floor depth produce a deterministic seed for the individual floor.
05 — Cavern Layout
The generator creates the floor's rooms and cavern shapes within the selected depth parameters.
06 — Paths & Topology
Rooms are connected into a traversable network with winding corridors and alternate routes.
07 — Resources & Environment
Resources, environmental features and other floor content are placed according to the active depth profile.
08 — Floor Identity
The completed floor receives its deterministic identity, allowing the same underlying floor to be reconstructed when revisited.
Implementation Level Breakdown
* The images shows the implementation level detail, steps may be different from the pipeline above
5 Floor Rolling Memory
The system uses a RAM logic that dynamically holds up to 5 temporary generated floor in its memory to ensure that players should visit any temporary floor outside this memory, that floor is completely recreated using its depth profile. It’s the current floor plus the latest visited four floors.
Active Memory Demonstration Slider
Chapter 05
Hazard Gates
Ooo, remember we told you about the dangers...? They sometimes lurk in the deep. But fret not! Our trustworthy Guild for Otherworldly Neutralization and Eviction (G.O.N.E) will notify you once you reach at a level that has a hazard beyond it whether it’s a toxic gas leak, flood or.. you know... Dermin swarm. Once you see the notification, kindly pay the fees for the heroic adventurers and wait for a day or two so they can fix your problem.
“A progression gate that interrupts deep descent and sends the player back to the surface to arrange clearance”
Challenge
Players needed to feel the progression towards depth are earned and access should feel like reward rather than continuously progressing without any cost at all.
Approach
Treated hazardous descent points as global progression gates. Once an uncleared hazard is encountered, all further descent is blocked. Clearing the hazard through the appropriate mercenary contract records a persistent clearance flag that remains valid across sessions.
Outcome
Exploration can be stopped for play time to get invested in other systems: Crafting and Shopkeeping.
How a Hazard Gate Works
01
Reach a New Floor Entrance
The player tries to descend into a previously unresolved floor.
Phase 01
02
Hazard Check
The system evaluates whether the floor contains a hazard.
Phase 02
03
Gate Activated
If a hazard is present, further descent is blocked. The player can continue mining the accessible floor or return to the surface.*
Phase 03
04
Mercenary Clearance
The player returns to base and hires the appropriate mercenary group using the required payment and materials. Mercenary hiring occurs outside the active mining session.*
Phase 04
05
Continue Descent
The cleared hazard is recorded globally. The gate remains permanently cleared for subsequent sessions, allowing progression to continue.
Phase 05
Note: A Hazard Gate ends forward progression, not the entire session.*
Hazard Types
Three hazard categories can interrupt progression:
Toxic Gas Pockets
Required Clearance
Alchemist mercenaries + required materials
Flooded Floors
Required Clearance
Aarinaq(1)-related mercenaries + required materials
Dermin-Invaded Floors (2)
Required Clearance
Adventurer mercenaries + required equipment/materials
(1)(2) Lore related content*
Hazard Occurrence
Hazard probability is evaluated when the player first reaches an unresolved floor. After a hazard is encountered, the probability cycle resets before gradually increasing again with forward depth progression.
Probability Progression Curve
Cap at Floor 8
Floors from last hazard gate (cycle resets after encounter).
Mercenary Clearance
Surface Economy Link
Relationship between the subterranean mine and the surface world economy:
01 HAZARD ENCOUNTERED
02 RETURN TO SHOP
03 SELECT MERCENARY CONTRACT
04 PAY FEE + REQUIRED MATERIALS
05 CLEARANCE COMPLETED
06 RETURN TO MINE
Subterranean Mine ⇄ Surface Guild Global state unlocked