Aliens & Asteroids: OSR-style Scifi Ranged Weapon

The other day I talked about a bit of the idea I had for combat armor in Aliens & Asteroids. This time I want to talk about a ranged weapon – the Pulse Rifle. We’ll probably have to change the name a bit, but let’s go with that for now.

Pulse Rifle

Essentially a Pulse Rifle is similar in use to a crossbow or longbow. However, there are a few pretty obvious changes:

  1. Most modern rifles require clips or magazines of ammunition. I’m looking at modeling it generally on a M16 rifle, which originally had a 20-round magazine. So right off the bat, a character with a rifle has the chance to fire up to 20 rounds before needing to reload. Though there have been improvements to the M16 magazine size, I think 20 rounds seems like a useful limiter for combat at this point.
  2. Later versions of the M16 also allowed 3-round bursts or full auto, firing numerous rounds at a target. As we’re roughly modeling a weapon along the lines of those used by the colonial Marines in the film Aliens, we want our Space Marines to also have similar capabilities for their pulse rifle. So in addition to a single-fire semi-automatic shot, they will have the ability to fire a 3-round burst or unload a full magazine at a target.
    • Single-fire mode can fire every round without difficulty.
    • Burst mode will only be allowed every-other-round before potentially requiring a cool-down period (roll 1d2 when two bursts are fired in sequential rounds – odd means it has overheated, then roll 1d3 for the number of rounds required). Assume that accuracy and damage are affected, so instead of d6 damage per round, it becomes d6-1 per round or 3d6-3. Maximum 15 damage. Minimum 0 damage.
    • Fully automatic mode requires a reload and a potential cool-down period (roll 1d2 – odd means it has overheated, then roll 1d6 for the number of rounds required). Again, assume that accuracy and damage are affected, so instead of d6 damage per round for any remaining rounds, it becomes d6-2 per round of ammunition, for a maximum of 20d6-40 or 80 points and a minimum of 0 damage.
  3. Some classes (i.e. Space Marine) will be able to reload as a free action. They have been so well trained as to make that action automatic, as long as they have clips to reload. Other classes must take a round to reload, like the good old crossbow.

Now I know these are some pretty significant changes. But let’s look at a potential scenario and see how it plays out.


Play Example

Let’s say we have a 1st level Space Marine PC with the following details:

  • HP: 8
  • Combat Armor: AC 14, AR 4, AP 14
  • Pulse Rifle: d6 damage, 20 rounds (single shot, 3-round burst, fully-auto)
  • 1 clip (20 rounds) loaded in weapon with two spares

And the Space Marine is going up against a single young Morph in the body of a rock-eating centipede-like creature.

  • HP: 18
  • Natural armor: AC 12
  • Attacks: Bite, d6; Claw, d6

Let’s give our young Marine the benefit of the doubt and she sees this ugly critter coming from 50 yards away, well within the effective range of the rifle.

  • Round 1: Alien distance 50 yards, Marine fires and misses (19 rounds left)
  • Round 1: Alien closes to within 40 yards (figure speed at 30 ft or 10 yards a round for now)
  • Round 2: Alien distance 40 yards, Marine fires and hits. 5 points of damage. Morph is down to 13 HP. (18 rounds left)
  • Round 2: Alien, now ticked off, runs double speed and closes to 20 yards.
  • Round 3: Alien distance 20 yards, Marine fires and misses (17 rounds left)
  • Round 3: Alien still pissed off, runs double speed again and closes to attack
  • Round 4: Alien at close range, Marine fires a burst and does 9 points of damage. Morph is down to 4 HP. (14 rounds left)
  • Round 4: Alien attacks Marine and hits, doing 4 points from the bite and 5 points from the claws. Armor absorbs 4 points, going to AP 10, and Marine takes 5 points, going to 3 HP.
  • Round 5: Alien at close range, Marine goes fully automatic with the rounds she has left. She hits. She rolls damage for 14d6 and gets 61, subtracts 28, and gets 33. Alien goes down in a mess of xenomorphic goo.

Of course, I hope the Marine doesn’t get any of the goo on her. That stuff stains!

The trouble may come with doing the math for the fully auto and burst modes, so we may have to come up with another way to handle that.

Seeking Feedback

What do you think? Figuring damage needs some work. I’m not sure that your average gamer has 20d6 lying around. 🙂

That said, I think that a running gun battle between a squad of Marines and an alien or six would be a heck of a lot of fun!

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