Deadly combat systems

[Jd Smith1]

Lets list the most deadly combat systems in the business; to qualify it has to be dice-based and a TRRPG.

Here's a short list to start:
Riddle of Steel: d10 pool combined with canned maneuvers. A lot of combat ends with a single exchange of blows, with one or both combatants dead.
Millennium's End and Aces & Eights: d100 and d20 system mated to target overlays, where a single solid hit can end the fight.
Zweihander and Flames of Freedom: d100 system with damage based on five stages, very little tactical healing, and any weapon strike having the potential to one-shot anyone.
Phoenix Command: Not only could it kill you with a single shot, but it could tell you the exact path it took through your body as it killed you.
Rolemaster, Spacemaster: Had the potential for a one-shot fatal crit in every attack!

 

[BigJackBrass]

Mercenaries, Spies & Private Eyes: Guns will seriously mess you up. So deadly that the game introduced the "Megadeath Luck Saving Roll" in an attempt to not just murder everyone.

 

[Umbran]

Most editions of Shadowrun - a properly constructed Street Samurai with a fully automatic weapon is pretty much a Hose of Death.

 

[John R Davis]

SPI Dragonquest. D100, roll low for grievous injury.

PF1 where a 1st lvl PC can kill themselves several times over with a crit.

 

[TheHand]

Early edition Stormbringer was pretty deadly. You had fixed maximum hit points that usually averaged around 11, and weapons did comparable damage numbers to D&D.

 

[MGibster]

Blue Planet 2nd edition had a fairly deadly combat system with a lot of versimilitude. You were pretty unlikely to kill someone by punching them, but once you broke out the submachine guns, rifles, and grenades, the odds of ruining someone's day went up quite a bit.

 

[practicalm]

GURPS is deadly. Guns and crossbows are not to be laughed at unless you are armored.

 

[GrahamWills]

Fate: A W:4 attack which rolls 4 higher than your defenses has you taking a critical injury. GM tags one more aspect than you can, and you're dead. especially nasty is hard sci-fi versions of Fate, such as Mindjammer. An augmented warrior with monofil blade is rolling at +4 better than you with a W:6. You are dead unless you have some way of counteracting.

 

[GrahamWills]

DramaSystem: If you have allowed a character who is you character's enemy to assemble enough tokens, they can effectively narrate you dead. (This has happened to me, but I lived long enough to get my murderer exiled. Family can be a real hassle)

Edit: Oops, OP required death by dice, not diceless systems, so DramaSystem does not qualify

 

[Cordwainer Fish]

Traveller. Your physical attributes are your HP, so as you take wounds your ability to survive and recover from wounds ablates; healing is not magic; and when you is gone, you is gone and no way, no how, is you ever coming back.