Painslayer

Painslayer is a gameplay mod for the GZDoom source port by Jekyll Grim Payne (aka Agent_Ash) that faithfully recreates several important facets of the  video game. Since Painkiller gameplay has significant differences compared to classic Doom, Jekyll needed to overhaul both the player's arsenal and movement. He also recreated the Tarot Card system of Painkiller.

Released in 2021, it has been praised for its high quality and fidelity to Painkiller. It won a Cacoward that year.

Features
Painslayer is a gameplay and weapon mod that aims to be compatible with any map and any monster sets, be it vanilla enemies or monster packs. As such, it doesn't come with any monsters, and the various gameplay aspects, while inspired by Painkiller, are tweaked to work in Doom. Painslayer heavily utilizes ZScript to achieve various technically complex effects.

Some of the key features are:


 * Painkiller weapons: Almost every weapon includes a primary attack, a secondary attack, and a tertiary combo attack The weapons are faithful recreations of the weapons from Painkiller and its add-on Painkiller: Battle out of Hell, with some tweaks to power or mechanics to increase their usability and make them feel more or less balanced on Doom maps against Doom enemies.


 * Black Tarot Cards: at the start of a map (or at a press of a dedicated key; configurable) the Black Tarot Board opens, where the player can purchase and equip up to two Silver Cards (they provide unlimited passive bonuses) and up to three Golden Cards (they can be activated once per level and provide very powerful bonuses for a short period of time). The cards can only be equipped once per map, after which they become locked in their slots, although they can be unlocked for extra money. In contrast to the original game, where the cards were unlockable by completing map-specific challenges, in Painslayer they can be simply bought for gold. Also, as of release 1.2.0, it's possible to restore golden card activations for gold, once they've been used in a map.


 * Gold: Used to purchase Black Tarot Cards. Gold can be obtained from breakable crates and explosive barrels, by gibbing enemies, and it also spawns dynamically in any sectors marked as secret areas on a map. Like in the original game, enemy corpses can also be juggled with Killer (the secondary mode of the first weapon), which makes them drop gold.


 * Souls: There are no health kits (medikits and stimpacks are replaced with various ammo pickups); instead killed enemies despawn after a short time and leave a soul behind. Taking a soul will heal the player; the amount healed varies between 1 and 20, based on how much health the monster originally had. The only traditional health pickups are Gold Soul (gives 100 health) and Mega Soul (gives 200 health and 200 armor), which serve as a soulsphere and a megasphere replacement respectively.


 * Demon Mode: Upon collecting 66 souls the player will turn into a Demon for a short period of time. Demon Mode makes the player completely invulnerable and replaces their weapons with a single attack that deals huge damage, one-shotting most enemies. The world will be colored in high-contrast black and white, while the enemies become red—this was made possible thanks to a . Enemies killed during Demon Mode do not leave souls. Demon Mode can be disabled from the Mod Settings.


 * Switchable fire modes: Imitating a feature from the original Painkiller, in Painslayer, using the built-in Mod Settings menu, the player can switch the primary/secondary fire modes for any weapon. It's usually recommended to do it for Rocket Launcher/Minigun, because many players find it confusing that the rocket launcher is a primary attack and not a secondary one.
 * In-Game Codex: Since a lot of the mechanics from the original game, such as power-ups or combo attacks, are somewhat obscure, the mod features a built-in Codex that provides information on all the weapons, items and key mechanics. It can be accessed at any time. When picking up a new item for the first time in a play session, a "Codex updated" notification will flash in the top-right corner (can be disabled in Mod Settings).
 * Russian localization: The mod comes with English and Russian support. That means that the Black Tarot, the Codex, the obituaries, item pickup messages and other text strings are provided both in English and in Russian; the players simply need to use GZDoom's built-in language setting to see the localization.

Weapons
The weapons in the mod are recreations of the weapons from Painkiller and Painkiller: Battle out of Hell, for a total of seven weapons. They use sounds from the original game, while the graphics are retro-styled hand-painted recreations. The following weapons are included:


 * Pain/Killer: The titular weapon that also serves as a starting weapon and as a replacement for Pistol, Fist and Chainsaw at the same time.
 * Pain: Deal continuous damage with the spinning blades in melee, similarly to Chainsaw.
 * Killer: Fire the blade unit as a projectile that can stick into walls. If the player faces the projectile (whether in flight or when it's stuck), a laser beam will be created from the gun body to the projectile, which burns enemies in its way. The projectile can also juggle enemy corpses; every third juggle makes the corpse drop a gold piece. Tapping the attack button again or switching to a different weapon will make the Killer fly back to the player and reattach itself to the weapon. (It can't be lost since it will fly through all objects and geometry.)
 * Pain+Killer: Hold Pain, then tap Killer to fire out the spinning blades as a projectile. The projectile is slow but deals a lot of damage. Upon hitting an enemy or a wall, it'll fly back to the player.


 * Shotgun/Freezer: A workhorse-type weapon with a powerful combo attack.
 * Shotgun: A fast-firing shotgun attack with medium damage and decent spread. Smaller enemies can be blown away very far if blasted at a short range, which is similar to the shotgun in the original game.
 * Freezer: Fires a slow-moving projectile that freezes enemies. Frozen enemies receive extra damage, especially from the shotgun. Doesn't work on bosses, arch-vile or enemies with +NOICEDEATH flag (for example, lost soul). If the enemy was set on fire by the Flamethrower (see below), the Freezer will instantly put out the fire.
 * Freezer+Shotgun: Fire Freezer, then quickly fire Shotgun to cancel the slow Freezer animation into a Shotgun blast. Weaker enemies tend to be one-shotted as a result.


 * Stakegun/Grenade Launcher: A beloved weapon from the original game that allows sticking enemies to walls in a satisfying manner.
 * Stakegun: Fires a stake that deals very significant damage and will actually stick enemies to walls (provided their mass isn't too large). The accompanying visuals are intentionally a bit comedic, making the monster's sprite flat if it's pushed against a wall.
 * Grenade Launcher: A fairly standard grenade launcher. The grenades deal about the same damage as Doom rockets.
 * Grenade-on-a-stake combo: Fire a grenade, then fire a stake into it to create a makeshift rocket. The resulting projectile deals a lot more damage than grenades or rockets. This attack works exactly the same way as in Painkiller, except it's intentionally made a little easier to pull off to increase its usability.


 * Rocket Launcher/Minigun
 * Rocket Launcher: Fires rockets, much like the Doom rocket launcher, except with more visuals.
 * Minigun: A fairly standard minigun. In contrast to the original game, it has a short wind-up period – this is made in order to differentiate it more clearly from the Assault Rifle (see below), which is slower but more precise. It's worth noting that the spread increases the longer the player holds the fire button.
 * This is the only weapon in the mod (and in the original game) that doesn't feature any sort of a combo attack.


 * Electro/Driver: A powerful and versatile weapon that serves as a plasma rifle and a BFG equivalent at the same time.
 * Electro: Fires a stream of electricity over a limited distance. Can latch onto an enemy within a short radius around the crosshair. Deals continuous damage and can stunlock weaker enemies very efficiently. Corpses of the enemies killed by Electro will be blackened and smoking, and will jitter on the ground for a bit, with electric sparks coming off them.
 * Driver: Fires a stream of projectiles. They deal medium impact damage, and after flying for a bit they will explode in flight; however, they do not explode on impact. That explosion is actually deceptively powerful, so while it's difficult to calculate the distance in such a way that the shuriken explodes next to an enemy without hitting them, the resulting damage is worth it.
 * Electric Disc combo: Hold Electro, then tap Driver to fire a whole electric disc "magazine" of the weapon. The disc will stick into an enemy or a wall on impact and will fire electric bolts at the nearest enemies, then explode after a bit. This attack is very powerful despite its relatively short distance, and multiple discs can be fired very quickly, even at the same enemy, making short work of bosses.


 * Rifle/Flamethrower: The first of the two weapons that were added in Painkiller: Battle out of Hell and didn't exist in the base game. It's decently powerful and easy to use. In terms of code and visuals it's one of the more complicated weapons in the mod, featuring multiple layers of fire effects drawn on the screen, real-time HUD sprite scaling and offsetting to create a rather 3D-looking recoil effect, and a swaying fuel tube under the gun that sways faster or slower in accordance with the player movement.
 * Rifle: An alternative to Minigun, with slower fire rate, but higher damage per shot and much tighter spread. The only downside is that after every 7 shots it pauses very briefly before continuing to fire again. It's a very efficient weapon against hitscanners, such as zombiemen and chaingun guys.
 * Flamethrower: A powerful, short-range attack. The flames can pass through enemies and set them on fire; burning enemies receive damage over time. If an enemy was frozen by a Freezer, the Flamethrower will actually deal decreased damage, first destroying the ice, then burning the enemy itself.
 * Fire fuel tank: Fire Flamethrower, then tap Rifle in order to use a combo attack and launch the fuel tank. The fuel tank is a slow arching projectile that explodes on impact with a shootable target, or after burning for a bit, dealing a lot of damage over a large area and spawning flames around. Before exploding fuel tanks are also destructible: they can be shot with the Rifle or any other weapon, or damaged by an explosion, causing it to explode immediately. Multiple fuel tanks can be fired next to each other, and when one of them explodes, it'll cause a chain reaction. Alongside the Electric Disc, this is one of the most powerful attacks in the mod.


 * Boltgun/Heater: The second of the two weapons that were added in Painkiller: Battle out of Hell, and a "big brother" of the Stakegun/Grenade Launcher, featuring similar attacks. This weapon features the largest number of unique sprites in the mod (58) due to a complicated animation of the bolts firing and reloading.
 * Boltgun: The primary attack fires five steel bolts in quick succession. They behave similarly to stakes, except they fly faster and in a straight line. They can also pin enemies to walls.
 * Heater Bombs: The secondary attack fires a volley of 10 small, bouncing bombs, that explode either on a third impact with anything, or immediately when hitting an enemy. While the individual damage and splash area aren't that high, 10 bombs can be devastating for enemy crowds (or for the shooter, should they stand too close or let the bombs bounce back at them).
 * Bombs on bolts: Similarly to grenades-on-stakes, firing Heater Bombs and then firing Bolts at them produces makeshift Heater "rockets" that deal a lot of damage. This attack, however, is difficult to pull off, and it's very hard to hit more than a couple of bombs per volley, so it's not particularly useful.
 * Scope: This is the only weapon in the mod that has a scope that can be activated with the Zoom key. The scope can be activated at any moment when the weapon is selected, even mid-firing, and when used, the bolts will be fired directly from the center of the screen, making them easier to aim. While not used, the scope graphic reflects the geometry behind the player.

Black Tarot Cards
Black Tarot Cards can be purchased and equipped on the Black Tarot board at the start of a new map or at a button press. The cards are taken from Painkiller and Painkiller: Battle out of Hell, with some redundant cards removed (such as cards with identical effects that only differ in power, or cards that wouldn't work well in Doom), and some of the effects are tweaked.

Black Tarot Cards are not available at the lowest difficulty setting.

Silver Cards
Silver Cards provide a continuous passive effect. The player can have up to two Silver Cards equipped at a time. The following cards are available:


 * Soul Keeper: Souls never disappear.
 * Blessing: Increase base health to 150.
 * Replenish: Receive double the ammo from ammo pickups.
 * Dark Soul: Morph into Demon at 50 souls.
 * Soul Catcher: Attract souls and gold from a distance.
 * Forgiveness: Use Golden Cards two times per level.
 * Greed: Receive 2x gold.
 * Soul Redeemer: Souls provide more health.
 * Regeneration: Regenerate Health 10 sec after taking the last damage.
 * Health Stealer: Receive a portion of damage dealt to enemies as health.
 * Hellish Armor: Regenerate Armor 10 sec after taking the last damage.
 * 666 Ammo: Start the map with 666 ammo of every type.

Golden Cards
Golden Cards provide a temporary bonus and can be activated manually, once per map. The player can have up to three Golden Cards equipped at a time. The following cards are available:


 * Endurance: Take only half the damage.
 * Speed: Move faster.
 * Time Bonus: Golden Cards last 15 seconds longer.
 * Rebirth: Gain full Health and Armor on activation.
 * Confusion: Confuse enemies.
 * Dexterity: Weapons fire 2x faster.
 * Weapon Modifier: Activate Weapon Modifier.
 * Steps of Thunder: Your every step damages nearby enemies.
 * Rage: Deliver 4x damage.
 * Magic Gun: Guns don't consume ammo.
 * Iron Will: You can't be hurt.
 * Haste: Enemies move 4x slower.

Difficulty settings
Painslayer features custom difficulty settings:


 * Slumber: double ammo from pickups, 25% of damage received, monsters have 50% health.
 * Daydream: x1.2 ammo from pickups, 50% of damage received.
 * Insomnia (default): standard stats for everything.
 * Nightmare: 80% of ammo from pickups, monster aggression increased.
 * Trauma: 60% of ammo from pickups, no cheats, monster aggression increased a lot, monster reaction increased, monsters don't spawn souls when killed.