Spinal Shatter

A retro-styled First-Person roguelite Shooter, inspired by Arcade Hard games of old. Originally developed for the BYU Game Development Club's Fall 2025 Game Jam, to the theme of "SPOOKY".

Fantasy

You, a lone sorceror, awaken in a dark, dank dungeon. The last thing you remember is the cackling of the wicked necromancer who had cornered and captured you. With no natural light to speak of, you conclude that the only way out is through. Armed with only your knack for spellcraft, you must now venture out into the darkness to chew through an onslaught of undead hordes, and grow in your magic power enough to claim your revenge, and your freedom...

this game is most like...

Aesthetic Inspriation

• DOOM (1993)
• Vampire Survivors

Mechanic Inspiration

• Vampire Survivors (VS)
• Halo Firefight
• DOOM 2016
• Hades

Game loop

Context: Map structure

A central hub connects to 4 hallways, in each of the cardinal directions, each with its own unique arena room at the other end. The entrance to each hallway is identified by a torch of a unique color. The torches being lit represents them being "open"/"active" to choose, while being unlit represents them being closed and unavailable. Also in the central hub are a number of interactable items and/or NPCs that modify game mode settings, or provide progression systems for the player.

At the start of a new run, or amid a run and directly after finishing a round and exiting its arena room, 2 randomly selected hallways torches are lit (excluding the one that was just completed, if any). Each of the lit hallways has a completion reward associated with it, displayed diegetically.

Each quadrant has a different visual and mechanical theme to it.

Scenario walkthrough

Introduction

The game begins. I am in the central room. Two of the 4 hallways have their torches lit, with an icon of some sort showing what the reward would be for me were I to go down that hallway into that room and complete the challenge beyond. I choose the path in front of me simply by going down into the chamber at the end of the hallway. Once I enter the room, its Door locks behind me, and the Round starts. The Round is comprised of multiple Waves of randomly selected enemies.

Enemy Spawning

Internally, the game is keeping track of the number of waves and rounds I have completed. Each successful wave increases the game's "budget" for spawning by a small amount, and each Round completed increases it by a significantly larger amount. It then spends this budget on a randomized selection of enemies utilizing greedy Knapsack algorithm for selecting the largest, most difficult (and therefore most expensive) enemies first, and filling in the rest with smaller and smaller foes until it's filled.

What happens after a round is beaten?

I beat some number of enemy waves with my life intanct, so I make it back through the now-open Door. It then closes behind me and the round ends, resulting in a payout screen that gives me a bunch of money. I am also granted the reward promised in the hallway before I chose it.

Then I re-enter the central hub and visit the Shop to spend some of the money I gained on acquiring upgrades for my character on this run.

After I'm content, I then pick another room and begin the loop again.

TL;DR

choose a hallway, enter a room, kill the monsters, get out, get paid, get buff.

objective

Don't Die for as long as possible, trying to last until the end

Lasting for number of waves instead of amount of time, but could have timed waves too set of waves in a room could end with a "boss"

Mechanics

Controls

KBM / Controller	action
WASD / leftStick	Move
Mouse / rightStick	Aim
LMB / rightTrigger	(Press) Attack / (Hold) Charge Magic
RMB / leftTrigger	Secondary Weapon ability (a.k.a. "Alt fire)
MB4 (maybe E? maybe Ctrl?) / rightBumper	Siphon
MB5 / leftBumper	EITHER : (Parry / Guard?) or (use consumable, like trap?)
Space / southButton	Jump (vertical)
Shift / eastButton	Dodge (Horizontal)
??? / northButton	???
F / westButton	Melee attack

Mana System

The player is a spell caster that uses mechanics from other FPS games. we want physics based projectiles that you can charge to make bigger/stronger, with enemies dropping the mana you need to cast. We draw from DOOM 2016, and be able to beat enemies in melee if you're out of ammo.

IDEA: a special melee attack and/or takedown type move that will cause the enemy to eject a bunch of extra mana, refilling your "ammo" and sending you on your way to doom and glory.

IDEA: melee always ejects mana from an enemy, so if you're out of ammo, you can beat it out of them no matter what. Then you still have to siphon to draw it in.

But how do you pick up all of these floating mana particles everywhere? That's where Siphon comes in.

Siphon

While the siphon button is held, firing new attack is disabled. Instead, you get a large vacuuming cone in front of you that draws in collectibles and pickups of any kind and slurps them in towards the player. I am considering it functioning akin to another of your weapons, but that seems like an unideal solution.

TBD: If Siphon, like any other weapon, has a main "charge" functionality, and a secondary Alt Fire. If it does, its alt fire would be in the form of: Expel / Guard / Parry / Reflect: Instead of inhaling, release a burst of energy outward that will convert any successfully reflected enemy projectiles into your own projectiles and get sent back in the direction you're aiming.

Control wise, right now it IS alt-fire (other trigger/MB) instead, it should be "another weapon", where pressing 2 will jump to it, or scrolling wheel will cycle through,

Healing

Here are three potential models based on your game's inspirations:

1. Aggressive & Resourceful (DOOM-style): Enemies have a chance to drop small health pickups, with larger amounts guaranteed from a specific action (e.g., a "glory kill" style melee takedown). The Siphon mechanic is a natural fit for collecting these drops. This encourages constant aggression.
2. Strategic & Scarce (Hades-style): Health is a precious resource. Healing is primarily offered as a chamber reward, a rare shop item, or from a specific boon. This makes every point of damage meaningful and every healing choice critical.
3. Preparation-focused (Shop-centric): Healing is performed almost exclusively at the shop between rounds via "refill health". This places a heavy emphasis on performance during rounds to minimize damage taken and save money for other upgrades.

Recommendation: A hybrid of Model 1 and 3. Core healing comes from aggressive gameplay, reinforcing your mana-from-enemies loop. The shop serves as a reliable, but expensive, fallback to refill health before a tough encounter. This provides both tactical expression in combat and strategic choice in the hub.

I think I agree with your recommendation for the Health economy. A hybrid of 1-Aggressive-Doom and 3-Preparation-ShopCentric sounds like the best approach. I think I imagine a separate station from the ShopCart, like an interactable HealingFountain (might look like a giant cauldron or potion) that costs money to use, costing more the lower HP you are (non-linear relationship), which simply refills your health to full for the listed price. I haven't decided upon HealthDrops yet, but if I do, I see no reason why they couldn't be similar to money and mana drops with multiple size types.

Powerups

There will be arcadey powerups that make you temporarily stronger. For instance, consumable traps to crowd control enemies, and buffs of various sorts.

Traps:

• Icy floor lowers friction, lose directional control
• Floor is Lava, take damage and lose mana
• Goopy floor, slowed down
• Spike ball rolls through and knocks back

temporary buffs:

• infinite ammo
• invincibility
• Invisibility while not attacking
• super speed

Challenges

There are a number of ways to increase the risk/reward factor quite literally. Make the game harder, and increase reward multipliers.

Base game difficulty

This is a global modifer to enemy damage dealt, health, potentially an AI aggressiveness factor, and an increase of a global reward multiplier.

- D0_Braindead,
- D1_Easy,
- D2_Normal,
- D3_Hard,
- D4_Expert,
- D5_Brutal

THOUGHT: Tiers within the secondary challenges... such as "no damage" --> "1 hp", or timer having less and less time and reaper getting faster, 10m -> 5m -> 2m.

Timed mode

A cursed Hourglass sits on a shelf in the central hub room. Activating this will enable a timer for the main combat arenas. Completing a round within the time limit will award increasing bonuses based on how much time remained, with less bonus the closer to 0, and more bonus the less time it took. If the timer runs out before the player clears all waves, a larger reaper-like enemy will appear and slowly move towards you, permanently accelerating its movespeed at a very slow rate (with time), but susceptible to all the player's crowd-control effects (knockback, stun, slow, root in place, etc.). If the player manages to clear the rest of the waves and finish the round, without getting one-shot killed by the Reaper, then they may try to escape out the room's door, locking the reaper in behind them. They get no time bonus if this happens, but their run may continue. The acceleration bonus of the reaper stops accruing once the round is over, but it persists to what it ended at the next time it spawns at a timeout (i.e. speed starts at 1. time runs out, speed accelerates up to 5 before the player escapes, then freezes. the next time the reaper spawns, it starts at 5 where it left off).

Timed mode can be enabled from the central room any time it is disabled. It can only be disabled with a small (increasing) gold fee.

Masochist mode

1-HP challenge. If you get hurt, you die. Instantly, period. Must be enabled before the first round starts, and cannot be disabled until the whole run is over from success or death failure. Highest reward multiplier.

Streaks and bonuses

If you have a challenge enabled, there is another multiplier that starts to accrue on the SECOND time getting its bonus, that increases (likely to a cap) for continuing to get it round over round. The moment you fail the challenge, the bonus is lost/resets. For instance, clearing 3 timer challenges in a row might build up to a 1.3x reward multiplier, but if the timer runs out and the reaper spawns, then the bonus is reset to 1x.

In addition to timer, there is also damage-taken as a "penalty" type bonus. In other words, you start with a max amount of bonus that gets subtracted for each point of damage you take, making it zero out once you have taken 100% of your max life in damage (healing mechanics would let you persist, despite bonus lost). But if you did the challenge perfectly, with zero infractions, then you get a fixed "PERFECT!" bonus on top of that.

The Shop

Shop accessible in the central room
randomizes stock every time a wave is completed

MAYBE: close the shop up after you've bought something?

the more rounds you have completed, the higher the quality of shop items, including finding items at higher ranks, but at a discount.

Be able to sell existing perks in your inventory, allowing you to "trade-in" for replacements

What To Buy

2 permanent shop items: refill health/mana, maybe something else
3-5 randomized items (TBD), with the option to freeze one between rounds so you can save for something you like

And maybe a health potion Still deliberating on the health economy

Item Types

Spells a.k.a. Weapons a.k.a. Attacks

in this game the weapons / abilities are all spells. every spell changes how your attack works.

Main weapon: spammable, can alternatively charge Secondary slot: can only Alt-fire, but can use main charge (interrupt main charge with alt-fire press) Automatic ("passive") slot: periodically fires on a timer cooldown out of your control, for free. (I imagine some visual representation of it floats in front of you by itself, so you can see what it's doing).

do you have a limit on inventory size?

— 3:25 PM Primary weapon Alt weapon And I think I said 3(?) passive slots

Weapon ranks

Every weapon can rank up by purchasing copies of it again from the shop. Higher rank cost more but also sells back for more.

example ranks from Vampire Survivors, which start at level 1, and level up to 8, ranking up 7 times:

1. axe base: damage 20, pierce 3, count 1

2. count + 1

3. damage + 20

4. pierce + 1

5. count + 1

6. damage + 20

7. pierce + 1

8. damage + 20

9. knife base: damage 7, pierce 1, count 1

10. count + 1

11. count + 1, damage + 5

12. count + 1

13. pierce + 1

14. count + 1

15. count + 1, damage + 5

16. pierce + 1

In my game, in whatever form the inventory takes, there will be a level int associated with a given owned / equipped weapon. I want each weapon's SpellData to have an array of RankUps which have (or are themselves) a Dictionary between a StatType and the value it will be SET to when it levels up... Then level max is determined by array length, and each rank up simply goes into the array RankUps[level]. This allows any rank to modify any number of stats.

List of Weapons

FIRE Orb: bounces, main attack

• charge: increases size, damage
• ALT FIRE: Explodes on impact, effectively a rocket launcher with high knockback
• Automatic: VS "Wand" equivalent, fires at the nearest enemy.

WATER Slash: horizontal slice wave

• charge: increases width: individual hit chunks, decreases damage
• ALT FIRE: Spin attack / Nova, sends everything out away from you
• Automatic: VS Whip, attacks repeatedly around you.

WIND Wall: upright and flat, offensive shield

• charge: increases size, lowers damage, higher defense: individual hit chunks. lower charge is denser, higher damage
• ALT FIRE: Shield Bash/Charge moves quickly, massively increases knockback directly away from you, lowers damage
• Automatic: [TBD] might just be some ongoing defensive effect, like Laurel

POISON Spikes: shotgun, shatters on impact into smaller projectiles

• charge: increases ball size->number of shatter "generations", child, grand, etc.
• ALT FIRE: Bundle of Toxic Caltrops
• Automatic: VS Santa Water+ - fires a caltrop bundle up into the air, which comes arcing down. If the bundle hits a target directly it crits. If it crashes into the down, it opens the bundle and the cluster leaves behind a DoT field (alt fire).

LIGHTNING Lance: 3-hit spear thrust in a wide 90 deg cone (left 45 mid 45 right); can be sniper-ish

• charge: Zoom-in, cone width narrows, delay between strikes shrinks, length of spears increases. precision damage--high crit, smaller hit box. full charge becomes one large piercing beam.
• ALT FIRE: ... stun beam? charge attack?
• Automatic: VS Lightning Ring - periodically nuke a single nearby target with a divine smite/lightning strike from above.

ICE Storm: Constant AoE damage

• charge: continual drain to deal high consistent damage while channeling in a radius around you
• ALT FIRE: Energy stream, continuous steady damage in a cone in front of you, pushes or slows slightly
• Automatic: normal garlic behavior - radiate AoE damage in a circle around you at a tick rate

WOOD Chakram: boomerang, bounces between targets

• charge: increases number of bounces before returning
• ALT FIRE: Bolas, roping together bounce targets, drawing them into their central location upon the "return" trip
• Automatic: VS Bible - orbits around you, chopping and knocking back nearby enemies

ARCANE Missiles: volley of 3 small high damage pts, a la Model PX or VS Knife; charge Arcane Mage, locks on to targets

• charge: turns into lock on, increases missile / lock-on count
• ALT FIRE: Lift / pull from ME, zero gravity bubble from KH, suspends targets in the air helplessly visual differences to differentiate
• Automatic: fire a (rank-scaling) number of missiles evenly divided among enemy targets in range, on a timer.

mana drain? self buffs?

Ideal Start of the Game

You start with a 2 random weapons presented to you for free And then you can decide which slot to put them in: Main, Alt, or Passive

Stats

Up to 3 slots for unique items that provide persistent Player Stat bonuses -- they can also be ranked up on reqacquisition, like weapons.

• max health (additive bonus)
• max mana (additive bonus)
• move speed (multiplier)
• Armor (fixed, additive damage reduction)
• money drop rate (multiplier)
• pickup radius
• Jump Height / Air Jumps
• Siphon Range
• Siphon Speed
• Projectile Speed (multiplier on ValueRange)
• Projectile Size (multiplier on ValueRange)
• Projectile Count (additive integer)
• Charge Speed (some kind of % multiplier that makes your charge duration take some % less time; should scale relatively slowly)

Meta Upgrades

The "lite" part of "roguelite".

Save-file bound "permanent" upgrades that combine with the player's hard-coded minimum stats. You can spend some currency to buy these ranks between runs. There is a bonus These bonuses each have an associated toggle state to tentatively disable them individually, which does not lose their progress, but simply stops them from applying, reverting to min stats, until turned back on.

"Account" progression, grows slower than boosts in-game, stacks with in-game boosts.

Unsure of the design of how these are unlocked, if it's a "meta" currency, or if it's the same as Gold.

Types

One bonus for every Passive Stat at least. Additionally, Anti-RNG effects that make build-manipulation easier.

• Reroll hallway rewards
• Reroll shop
• Freeze charges
• Banish ? (maybe, only valuable with large item pool)
• Sell Value ratio - up to at most 100% of original cost, TBD

Enemies

enemies are described by a combination of several attributes:

SIZE: small(or medium, counts in the same size category) or large

MOVEMENT: GROUND or FLYING

RANGE: MELEE or RANGED(variable distances, but all projectile type attacks greater than melee range)
2 * 2 * 2 = 8

That is all that defines the core unit types / varieties, is these combinations. 4 Small types, and 4 large types. Then ALL of these units can have simple "artificial-difficulty" ranks, or difficulty tiers. Rank 1 is easy, 2 is normal, 3 is hard, and 4 is brutal. They will be simple reskins that make them measurably stronger, with more health and damage, probably speed, and an aggressiveness factor. Perhaps they may even unlock extra abilities.

RANK:
- Tier1_Bone,
- Tier2_Cloth,
- Tier3_Iron,
- Tier4_Obsidian,

Unit Name	Priority Objective	Speed	Size / Armor / HP	Movement	Attack Range	Attack Rate	Attack Damage	Spawn Cost	Description	Inspiration Reference
Scrounger	Ship/Cargo	Fast	Light	Grounded	Melee	Fast	Low	0.5	Tenacious pawns, brainless cannon fodder	WarCraft Ghouls, Destiny Hive Thralls
Scrapper	Ship/Engine	Medium	Medium	Grounded	Variable Range	Medium	Medium	1	Assault solider. Can wield any ranged weapon.	SW Battle Droid, Destiny Hive Acolytes, Destiny Vex Goblins
Lunker	Player	Medium	Heavy	Grounded	Melee	Slow	High	2	Front-line Bruiser, Normal walk, SLOW melee attack	LotR Troll, Overwatch Reinhardt, Warcraft 3 Mountain Giant, Destiny Hive Knights
Buster	Ship/Engine	Slow	Heavy	Grounded	Mid Ranged	Fast	Medium	4	Heavy Artillery, SLOW walk, fast midrange attack	Team Fortress 2 The Heavy, Overwatch Mauga
Swooper	Ship/Cargo	Fast	Light	Flying	Melee	Medium	Low	0.5	Buzzing flies, vultures, pests, thieves	SW Geonosian, Stormgate Spriggan, Warcraft Harpies
Zapper	Player	Medium	Medium	Flying	Long Ranged	Slow	High	2	Flying Snipers.	Mass Effect Geth Hopper
Boomer	Player	Slow	Heavy	Flying	Mid Ranged	Fast	High	3	Death from above, the Flame Comes.	SW Flametrooper, Yer average firebreathing dragon
Shredder	Ship/Hull	Medium	Medium	Flying	Melee	Medium	Medium	3	my what huge CLAWS YOU HAVE	Metroid Dread Emmi with Wings, tears things apart with ease