There should be no disagreement: Doom is one of the best games ever made. I like to describe it as a perfect killing engine. Every part of it works in concert to create something you just want to deal death in. Over and over again. It’s fast, violent, uncomplicated, but deceptively nuanced. Two decades later it still holds up because every piece of it pushes toward its goals.

That doesn’t mean there is no room for modernisation or improvement. Mouse look, engine fixes and modern level design via custom-made map packs are a massive boon to playing Doom in the 21st century. But there are some modern shooter tropes that would be unacceptable - not objectively awful, but desperately ‘not right for Doom - if added. I’ve picked out a few that would be especially heinous crimes if visited on id’s reboot. Pray that none of these turn up when the game is revealed at .

Doom’s most basic enemies - the Zombieman, Shotgun Guy, and Chaingunner - are not there to prove a challenge. There is a reason they are the only enemies to drop ammunition while every Pinky Demon, Spider Mastermind and Revenant leaves nothing but a delightfully colourful corpse behind: they’re interactive ammo dumps, there to be harvested as much as fought. They’re not just enemies. They have a very specific design purpose.

Now, this doesn’t mean they shouldn’t be a threat. An unchecked Chaingunner will reduce you to swiss cheese in moments, and an ignored Shotgun Guy is happy to make mincemeat of your back. But they cannot take the same punishment they deliver, single shotgun blasts felling scores of zombies (more on this later). Even higher difficulties have no effect on this: the wall of meat may be deeper, with more enemies to cut, blast and melt through, but it never takes longer to get through a layer. That’s vital to Doom’s unique pace and flow.

Doom is packed with enemies. If going for 100% runs at levels, you will regularly be blasting away hundreds if not thousands of hellspawn in a half hour period. Equally, they will not come at you one at a time, but in waves, seemingly unbeatable hordes teleporting on top of you with every grabbed key and opened door. Even the Cyberdemon, Doom’s rocket spewing boss creature, feels underdressed without at least a milling crowd of Imps to distract you, absorb your ammo (at the cost of their oen lives, of course) and trap you in a fatal corner. Again, this stuff is fundamental to Doom’s deceptively strategic flow.

Small battles can be used effectively, especially when introducing a new beast. The first episode of Doom finishes with the ‘bruiser brothers’ - a pair of super-deadly, high HP Barons of Hell - stepping out of the walls and assaulting the player joined, only by a few unthreatening Spectres. It’s a memorable moment precisely because it’s so rare, and Barons make all haste to join the rest of the cast in assaulting you en masse later on.

The heroic Doomguy is a man of strong back and many arms. There is no gun that he cannot find a place for somewhere on his person, and he does not need to discard his pistol, no matter how pathetic it may be, to pick up that Super Shotgun, Rocket Launcher or holy BFG. He is no ordinary marine trotting through Call of Duty: Demonic Warfare. Realism went out the door around about the moment the dead started coming back to life.

A varied and always accessible arsenal is a core part of Doom, and an important support strut for its excellent level design and ever-changing situational demands. Each weapon has its place and purpose, be it the Chaingun’s exceptional room clearing ability, the Rocket Launcher’s insta-gibbing of grouped targets at any range, or the BFG’s unique position as a panicked ‘oh fuck’ key. Constant, reliable access to these options is vital, especially if ammo is running low. Plus, the idea of having to pick between the Super Shotgun and Plasma Gun frankly reduces me to tears. Speaking of which...

If Doom is the best FPS of all time, then the Super Shotgun (SSG) is the greatest gun of all time. Forget the more realistic, speciality weapon you may be used to today, throw away the ineffective-at-medium-range ideal. Come sit by the burning demon corpses and let me explain. The SSG is an icon of death, a beautiful blunt instrument for reducing enemies to nothing. Its inclusion in nuDoom is mercifully already confirmed, by way of half of that recent being dedicated to it. What’s important now is that they get it right.

The SSG does more damage than a rocket launcher if all of its pellets hit. Faced with a squad of twelve zombies in two ranks, the SSG will annihilate them in a single click. In enclosed spaces, demons - with all their spiked carapaces, and claws, and three foot mouths rimmed with thick teeth - have nothing on the SSG. It is their god of destruction, your saviour, and every shot fired should fired from it should leave you with no doubt that something on the other end is experiencing Hell on Earth.

This is two-fold. On the one hand, the idea of pressing a button to get into cover is antithetical to what makes Doom. It is, basically, too complicated. With Arachnotrons turning the air green with plasma from half a map away, Mancubi shelling you to within an inch of your life, and the glowing eyes of Spectres bearing down on you with every passing second, you do not need to be worrying about whether the game has decided you’re hiding or not. If there is a wall between you and the bad guys, you are safe, if there is not, you better be moving.

You see movement is another big part of the Doom equation. Like in the many deathmatch FPS that followed, remaining static in Doom is a death sentence. The vast majority of enemy fire comes from big, clear projectiles that can and should be dodged, allowing you to close the gap or find an alternate route. Ducking in and out of cover is an act of sprinting between safe zones, not finding a good camping spot. Cover in Doom is actually about encouraging movement. It’s about speed and freedom not, well...

Doomguy does not get tired. He does not need a wee rest after running the 100 meters. Doomguy has a walk-key for being optionally careful, not a run-key for getting somewhere optionally fast. He gets everywhere fast. He is Usain Bolt on a specially concocted IV drip of jet fuel, energy drinks and exploding suns. Doomguy will stop when he’s dead. And even then, only for a bit.

If all other pieces of advice here are discarded, let this one remain. It is vital to the Doom experience that you move quickly, constantly. Not only in comparison to the size of levels, but in relation to enemies as well. They don’t get to run away, and you will outrace all but the most deadly projectiles. Not only that, side-stepping fireballs and even melee attacks is a bigger ego boost than all the perfect headshots in the world. Outnumbered, and even rarely outgunned, Doomguy is never, ever outpaced. That’s what it’s all about. That’s Doom.

The protracted, cinematic cut-scene is perhaps the least Doom thing in modern gaming. Don’t get me wrong, I enjoy being told a story as much as the next functioning human being. But I don’t need a reason to shoot a seething horde of anathema in their evil skulls. They are the eternal Bad Guys; that they were summoned here by the machinations of some foolish scientists messing with teleportation (or, Satan forbid, ‘unlocking the 24th chromosome’) is largely irrelevant. Now that they’re here, they just need to die, and I have the tools to make them die.

Going to the extreme of the original games’ end-of-episode wall o’ text isn’t an option in 2015, but thirty-second cutscenes that inject some purpose or a sense of place will be very welcome. Tell me where I am, what happened here, and what I’m doing next, but never wrest control from me for too long. All should be skippable, with any additional exposition hidden away as Dark Souls-like environmental secrets, or inserted into the UI in some unobtrusive and easily ignored way while I’m clearing another room of hostile hellspawn.

Nobody in Hell likes everyone else in Hell. They don’t like anything - they’re in Hell. Doom’s monster in-fighting proves that the forces of evil are inherently racist, and the gameplay is all the better for it. Why would a Mancubus, fatty hide charred from an errant fireball aimed at your sprinting form, not turn his cannons on the foolish Imp that threw it? And when his aim falters and takes out half the advancing line of Pinky Demons, why wouldn’t they become distracted for a moment to chew his rebellious little face off?

This sounds like an impossibly intelligent AI fantasy-land but it was all possible, common and downright fantastic in 1993. Without the benefits of in-fighting, ammo would quickly become a scarce resource and, presumably, even your ringed knuckle would fall off from overuse eventually. Beyond that, it’s just bloody fun. It’s another way in which you’re smarter than your enemies, able to manipulate them to your will and make them take each other out while you’re in another part of the level. And it just makes Doom even more brilliantly, cleverly chaotic.

Through Doom’s impressive bestiary there is precisely one reskin, not counting invisible variants of other enemies. The Baron of Hell is the bigger, tougher, red cousin of the Hell Knight, with twice as much HP. That’s it. He’s the only reused monster. While you will kill hundreds of each type of enemy throughout a campaign, each is so different from the rest - in both look and purpose - that it never gets old.

The ultimate example of this is the Arch-Vile. The flickering flame decal that obscures 90% of the screen is a warning sign that one is nearby and locked on to you. Break line of sight immediately or take a crippling amount of damage. Out of its way? OK, it will now start resurrecting its slain friends, creating a wall of very angry shielding to get through before you can directly damage your main foe. They are nothing like any of their Hellish compatriots. Correct deployment of Arch-Viles in custom maps makes powerful memories. Every enemy in Doom has similar possibilities and uses, and that should - in fact must - continue.

Perhaps Doom’s most underappreciated factor is its colour. Behind all the gore, the wonderful selection of weapons, and the brutal bestiary of enemies is - usually - a lovely Technicolor texture. There is chrome, and mud, and even sewer levels in both original games, but the water is a deep blue, the chrome a glowing silver, and the sparsely-used dirt such a disgusting shade of brown that you can’t help but marvel at it.

This is partly due to the technology of the era. Enemies, danger areas, and pick-ups all have to be easily parsed at resolutions that would make your 1080p-accustomed eyes bleed. More than that, maps are so large and open that objects regularly have to be identified at long range. The upshot of all this is that every sprite and texture is still instantly recognisable, partly caricatured out of necessity, but dripping with personality as a result.