Category Archives: design document

15 Minutes: WIP Design Documents


This is a work in progress. It describes the basic design concepts that I have already got down for the 15 Minutes game, but nothing described here is set in stone. It’s also not really written for the public audience, so although you should be able to get the gist of what I’ve got in mind for the game from reading this document, you may misinterpret some of my notes or short-forms as they were written as a reminder for myself, rather than with anyone else in mind. I’ll try to go through and tidy things up periodically, but for now it’s a bit of a mess.


  1. ARPG
  2. Fast paced
  3. Time limited (i.e. 15 minutes)
  4. Random generated tileset dungeons
  5. Rogue-like (permadeath)
  6. Different classes with different playstyles
  7. Diablo style control scheme/playstyle

Classic roguelike dungeon diving but real time rather than turn based, and time constraints to really put the pressure on the player to rush. Add traps and/or puzzles that would be quite easy to deal with if you had plenty of time, but which the player is at risk of screwing up because they’re rushing. i.e. Swinging blade trap – easy to time it right if you’ve got time to think, but hard when you’ve got serious time pressure.


3 classes with genuinely different playstyles

Stealth/speed based (Thief)

Avoid or backstab most monsters, so that you don’t get delayed with face-to-face combat that you’re not well suited to, better at traps/puzzles due to movespeed.

Strength/combat based (Fighter)

Murder monsters fast, but slower movespeed and more difficult to get through traps/puzzles.

Magic based (Wizard)

Range-limited teleportation, ranged spells, squishy. Needs to make very smart engagements or will die easily. Can skip some traps/puzzles though! Need to manage mana usage or risk being very vulnerable.

Player is trying to get to end of dungeon

Beginner players should have about a 1/20 – 1/30 chance of making it to the goal within the time limit. Intermediate players should get up towards a 30% chance. Skilled players should get towards 50%. Master players should be able to make it around 75% of the time.

The dungeons should be maze-like, but not difficult mazes

Don’t want to frustrate the player with “shit shit shit how do I get to where I need to be”, but also don’t want it to be obvious where to go.

XP progress should be quite rapid if you’re killing stuff

Difficulty of each level as you descend into dungeon should also scale quite quickly. Players who rush downstairs too fast are taking a big risk of dying. Players who mill about levelling up are taking a big risk of running out of time. This also addresses one of the big issues I have with most rogue-likes where players get attached to their character over time and it crushes them when they lose a good one that they invested a lot of time on.

Beyond just “reaching the goal”, there should be leaderboards for how quickly you can reach the goal.

These should be broken down per class and per special win conditions. i.e. NetHack style pacifist runs, naked runs, vegetarian runs, no potion runs, etc. Add a sense of community competitiveness and adds a lot of replayability for those players who have gotten good at the game and want to increase the challenge.

Should be relatively easy to add different game-modes.

i.e. 10 minute mode, 20 minute mode, 30 minute mode, which have more levels to descend. Different leaderboards for each mode.

General rule of thumb is to put the player in situations where they must choose between speed and safety.

As the time pressure mounts they will be forced to make some dicey decisions.

Potential nice-to-haves that should be considered during design

  • Co-operative multiplayer?
    • Diablo style – more enemies that are scaled up
    • Potentially frustrating waiting for a friend who has a more cautious playstyle than you?
  • Top down third person control scheme and also first person control scheme options.
  • Different leaderboards. Perhaps one class is first person while another is third person?
  • Oculus rift support?


Very self-aware, tongue in cheek mood. A lot of things about the design make no sense – why would there be a shop in a dungeon, and why would the shopkeeper still be running it if the world is about to end? Why would the player get hungry, he’s only got 15 minutes? etc. The game should be aware of the fact that these game design considerations are exactly that, they’re to facilitate a certain type of gameplay and they don’t really make sense.


  • Monsters
  • Waypoints – paths for some monsters to patrol (aids the stealth based gameplay options)
  • Chests – loot droppers
  • Special tiles –
    • stores,
    • special quests,
    • special opportunities (shrines? Fountains?)
    • Traps


  • Should spray out when you open a chest or kill a monster, Diablo style. No goofy slow container system.
  • Arrows
  • Money (can be spent at stores)
  • Health and mana potions – insta hit restore.
  • Cure potions – remove DoT effects when drunk
  • Food – slow release timed restore with limited efficacy. Also restores hunger.
  • Equipment/weapons
  • Smoke bombs (for stealth character)
  • Monster essence – restores a fixed amount of health or mana when you kill the monster and loot them. i.e. Fighter archetype gets a certain amount of health back from killing, magic archetype gets a certain amount of mana back from killing. Stealth archetype gets nothing?


  • Chest – primary damage reducer
  • Helm – secondary damage reducer
  • Boots – minor damage reducer and minor movespeed increaser
  • Ring – minor attack damage increaser and special effect giver
  • Amulet – minor attack damage increaser and special effect giver

Equipment gets RNG stat rolls.

All equipment rolls are monster level based. Min/max values defined.


  • Long blade – hi sharp damage, slower attack speed
  • Short blade – lo sharp damage, faster attack speed
  • Axe – mix of hi blunt and sharp damage, slow attack speed
  • Mace – blunt normal damage, normal attack speed
  • Hammer – blunt hi damage, slow attack speed
  • Bow – ranged attack, lo sharp damage, consumes arrows.

Larger weapons have lower concealability for stealth mechanics. Short blade (daggers) best for this, but lowest damage.

  • Wands (spellcaster only, low damage fast attack speed)
  • Staves (spellcaster only, high damage slow attack speed)

Fighter – str primary stat

  • Prefers melee combat (cannot equip bow?)
  • High health
  • Recovers health from kills
  • Slower move speed
  • Higher detection radius (harder to avoid monsters, and to prevent multiple monsters from seeing and attacking)
  • Armor/health based face to face combat – i.e. Armor mitigates/absorbs damage to reduce its effect, with ways to improve armor?

Thief – dex primary stat

  • Two move modes – sprint or sneak.
  • While sprinting detection radius is similar to fighter, but move speed very high
  • While sneaking detection radius is much lower, but move speed is very slow
  • Can sneak behind monsters to do very high damage opening moves (backstabs)
  • Quite poor at face to face combat
  • Dodge based face to face combat? i.e. If hit take lots of damage, but chance to dodge and take none, w/ ways to improve dodge chance?
  • Can use smoke screen skill to evade monsters once detected?
    • This would break monster detection and make the stealth character invisible for a very short time, and also switch them into sprint mode so they can escape

Wizard – int primary stat

  • Two move modes – Range limited teleportation or walking
  • Teleportation is instant, but consumes mana
  • Walking is fairly slow
  • Terrible in melee combat. Low health. Low hand to hand damage.
  • Ranged combat with kiting preferred. But player must consider how much ground they are losing, and conserve mana. May opt to use bow but lower damage than spells.
  • Recovers mana from kills, and very very slowly over time?
  • Can use carefully timed shield spells to mitigate damage in exchange for mana.

Hunger system

  • Hunger gradually builds over time, can eat foods to reduce
  • If hunger gets too high reduce attack damage and move speed
  • If hunger maxes out start taking damage over time

Stealth system

  • Players have detectability value – this controls how fast before monsters are alerted to their presence once the monster can “see” the player
    • Heavier armor and weapons increases the detectability value. –  similar to Payday 2 concealment
  • Monsters have detection radius value. In front of them this is full, behind them this is reduced to ~1/4.
    • Once player is in the detection zone for that monster they start detecting the player… But only start pursuing/attakcing the player when their detection meter hits a threshold
  • Players have a detection radius modifier i.e. Fighter = 1.0x, stealth sneaking = 0.5x, stealth sprinting = 1.1x. This can be further altered with skills?
  • Detected players will be pursued by the monster for ~5 seconds (perhaps have different memory time for different monsters, i.e. Some pursue the player more dilligently than others), but if the player continues to be detected then this will be constantly reset back to zero.
    • This allows the player to attempt to evade the monster. i.e. Spellcaster can teleport around a corner, Stealth character can use a smokescreen? However, if they cannot get out of the monsters detection radius they will continue to be pursued.



  • Slow, ranged, low health, low damage
  • Bullet hell type variants – i.e. Ones that do triple shot, fast projectiles, slow projectiles. Player can manually dodge.


  • Many variants
    • Tanky high health types
    • Small faster ones that tend to spawn in clusters. Low health and damage but swarmy.
    • Lower health higher damage types


  • Also ranged
  • Fire/ice/poison variants. Insta damage/slowing/DoT(curable)
  • Drop extra mana when killed.

Variety of detection radiuses and move speeds. Some should be kitable by walking spellcaster, others should be able to keep up with a sprinting stealth character.

Some should patrol predictably between a set of 1-4 waypoints (in each tile set 4-5 locations where waypoints can spawn, giving each a ~75% chance to spawn. Monsters spawning in the same area that want to patrol waypoints will seek out spawned waypoints and start using them as routes. Others should be stationary or just pacing back and forward over a short distance (changing facing direction, for purposes of stealth gameplay). This sets up stealth gameplay.

Some monsters more susceptible to blunt, some sharp, some magic.

Some monsters may attempt to dodge projectile attacks.

Monsters do damage based principally on the level of the dungeon they spawned on. Different monsters do damage in different ways.

  • “Normal” attack speed, average damage.
  • Wind-up and big hit. Very avoidable/stunnable/shieldable
  • Fast attack with small damage.
  • Ranged attack with small damage
    • Multi-projectile attacks with even smaller damage, dodgeable
  • Slow AoE projectiles with reducing damage depending on how far from center

Quest NPCs

“Help me defeat such and such to get a reward!”. Options i.e.

  • Spawns a random single “big” monster in the next level of the dungeon (i.e. Make the monster more tough)
  • All of a particular monster type in the next level.
  • Reward is triggered automagically when the player fulfills the conditions? (making them walk back to the questgiver would eat too much time?)
  • If player completes all quests they encounter (minimum 2) they get the “Heroic Adventurer” flag and leaderboard.

“I am hurt! Please give me a health/mana/cure poison potion!”

  • Random chance that they will turn out to be hostile or friendly
    • If friendly, player receives a reward
      • Random piece of equipment…
    • If hostile, player just gets into a fight with no special reward
  • If player completes all “I am hurt!” quests (at least 2) they get the “Red Cross” flag and leaderboard.

“I am stuck down a hole, please find a rope to rescue me!”

  • Rope will spawn in a chest at some point in the same level of the dungeon
    • Random item reward
      • Small chance (i.e. 1/4) they will end up being hostile, but you still get the reward for killing them.
  • If player completes all “I am stuck!” quests (at least 2) they get the “No Man Left Behind” flag and leaderboard.


Primarily timing based traps i.e.

  • Swinging blades
  • Flame jets/Ice jets/Poison jets
  • Arrow traps

These should be easy to avoid if you are willing to go slow, but require significant skill to successfully speed run through. Player must choose between speed and safety.

Also some pressure plate based traps, following same types as above, but easy to dodge – just avoid the pressure plate.

  • Harder to avoid pressure plates when fleeing monsters though!

Traps do increasing amounts of harm as the player progresses, but the various types of traps should range from low to high damage. i.e. Low damage traps do ~10% of an appropriately levelled characters health, while high damage traps do more like 50%. Experienced players should be able to easily identify which are low/medium/high, so they can make appropriate snap decisions about whether they are going to bother spending time to avoid the trap, or if they’ll just plough through to save time.

Traps should also damage monsters, but monsters will avoid traps unless pursuing the player. This way the player an lure monsters into traps for assistance with kills, but monsters won’t just spontaneously get themselves killed.

Control scheme

Diablo style. Click to move. Click to attack. Right click to defend (reduces incoming damage, limited use).

4 skill hotkeys. 2 potion hotkeys (health and mana, consumes potion).

Stealth and Fighter have a switch weapons hotkey (i.e. Fast swap from ranged to melee)


Default attack is simple melee if using melee weapon, ranged if using bow

  1. Sneak
  2. Sprint
  3. Backstab (only available when close behind an enemy ?and not in combat?)
  4. Smoke screen (break engagement, opportunity to flee, consumes smoke bombs)

Fighter – generates rage during combat, but rage decays out of combat

Default attack is simple melee if using melee weapon, ranged if using bow.

  1. Bash (short stun effect that interrupts attacks, consumes rage)
  2. Berserk (time limited increased damage and improved armor rating, consumes rage)
  3. Whirlwind (AoE with knockback and short stun effect, consumes rage)
  4. Leap (can jump over enemies to escape a surround, can only use during combat, can only use every ~3 seconds)

Wizard – generates mana very, very slowly.

Depends on mana recovered from fallen enemies.

Default attack is ranged fireball (does not consume mana).

  1. Teleport (range limited, consumes mana)
  2. Ice projectile (slows enemy move speed, consumes mana)
  3. Meteor (AoE high damage, consumes mana)
  4. Shield (timing based damage mitigation, consumes mana)

Levelling and character customisation

When the player levels they get a skill point to award to one of their skills to improve it. This allows a degree of character customisation, as you can focus on different skills depending on play-style.

Sneak – improve sneaking speed and further improve detection stats
Sprint – improve sprint speed
Backstab – improve backstab damage
Smoke screen – increase duration before monster starts to see player again

Bash – reduce the rage cost
Berserk – improve duration of skill
Whirlwind – improve AoE damage and reduce rage cost
Leap – improve leap distance and reduce cooldown

Teleport – improve range of teleport, reduce mana cost
Ice projectile – improve slowdown effect, increase speed of projectile, reduce mana cost
Shield – improve duration of shield effect, reduce mana cost
Meteor – improve damage, reduce mana cost

Player base damage passively improves as the player levels.

Player also gets points which they can invest in stats.
Str is damage stat for fighters, but also improves armor for everyone
Dex is damage stat for stealth, but also improves dodge for everyone
Int is damage stat for spellcaster, but also improves magic resistance for everyone
Vit improves base health for everyone.


(Base damage + Weapon damage + Primary stat damage) * Attack Damage Modifier
Equipped weapons improve player damage.
Primary stat (str for fighter, dex for stealth, int for wizard) improves player damage

Damage mitigation applied by Armor stat for physical damage
Damage mitigation applied by magic resistance (int) for spell damage

Thus, fighters will be vulnerable to magic if they dont invest points into Int. Spellcasters will be vulnerable to physical damage if they don’t invest points into Str/Dex. Stealth characters will risk the chance of being one-shot if they don’t invest into Str and Int. Etc.

Special tiles

– Drink from them to gain random effect
a. Restore health
b. Restore mana
c. Temporarily Improve armor
d. Temporarily improve damage
e. Poisoned (DoT)

– Shopkeeper sells an inventory of items in exchange for money. Limited stock.
○ Health potions
○ Mana potions
○ Smokebombs
○ Arrows
○ Cure poison potions

– Shopkeeper sells drinks
○ Drinks are just plain bad.
§ Lower stealthability
§ Lower attack speed
§ Lower health
§ Screen blur effect
○ Different leaderboard for alcoholic players
§ It’s a self-inflicted challenge for players
§ If they spend at least 1/5 of the total gamemode duration drunk (influenced by drink) then they get the alcoholic flag
§ Each drink lasts ~1 minute.

Traps (discussed previously already)

– Stuck in a hole quest NPC mentioned previously

Leaderboards and Achievements

Global leaderboard system should contain ALL completed attempts times and statistics. Local leaderboard should show all of your scores/times, not just completed ones.

Also daily/weekly leaderboards?

Each character gets a time alive, class, as well as a range of flags.

– Completed dungeon/Did not complete dungeon
– Vegetarian (has only eaten vegetarian food)
– Carnivore (has only eaten meat)
– No Man Left Behind (completes all stuck in hole quests – at least 2)
– Heroic Adventurer (completes all “go kill X for me” quests – at least 2)
– Red Cross Worker (completes all “I need a potion!” quests – at least 2)
– Trap Pro (takes no damage from traps)
– Pacifist (kills no enemies)
– Alcoholic (spends at least 1/5 of total gamemode duration drunk)
– Potions are for sissies (doesn’t drink any potions)
– Legolas fan (only uses a bow)
– Brute (only uses melee weapons)
– No Time To Eat! (spends at least 1/5 of the total gamemode duration at maximum hunger)
– Mad Hops (uses Leap at least ~50 times)
– So Dizzy (uses Teleport at least ~100 times)
– You’ll Never Catch Me! (uses at least ~30 smoke bombs)

Completing the dungeon with each flag is also associated with an achievement
Additional achievements
– Play as a fighter
– Play as a spellcaster
– Play as a stealth
– Complete as a fighter
– Complete as a spellcaster
– Complete as a stealth
– Equip each weapon type
– Equip each armor type
– Complete a quest
– Complete a stuck in hole quest
– Complete a heal me quest
– Complete a kill boss monsters quest
– Complete a kill all monster type quest
– Successfully stealth an entire dungeon level
– Successfully stealth an entire dungeon level as a fighter
– Successfully stealth an entire dungeon level as a spellcaster
– Reach xp level 2
– Reach xp level 5
– Reach xp level 10
– Reach xp level 15
– Reach dungeon level 2
– Reach dungeon level 5
– Reach dungeon level 8
– Reach dungeon level 9
– Reach dungeon level 10
– Die
– Die of poison
– Die in a trap
– Die of hunger
– Successfully backstab an enemy and one-shot them
– Use shield to avoid an attack
– Use bash to prevent an attack
– Use meteor to kill more than one enemy at once
– Buy from a shop
– Get drunk
– Kill 100 monsters
– Kill 500 monsters
– Kill 1000 monsters
– Stealth 5 levels
– Stealth 10 levels
– As a spellcaster kill a monster without taking damage

– Get top 10 in a daily leaderboard

– Get top 10 in a weekly leaderboard