Slaying the Target Outright

Question

In Dungeons and Dragons 4th edition's Player's Handbook I. on page 288 states:

Under "Coup De Grace," there is the rule "Slaying the Target Outright": "If you deal damage greater than or equal to the target's bloodied value, the target dies."

Does the above rule apply to standard combat or only for helpless targets and if Coup de Grace is performed? For me, it would be natural to apply it to any standard damage outside of Coup de Grace as well, since getting damage equal to my bloodied value seems like a devastating single hit, like losing a head or torso.

Example: "Am I a minion to you? (Relatively.)" - asks my Level 1 Fighter (with around HP value of 35, bloodied 17) to Orcus (Monster's Manual I., page 206), who deals average damage of 28. It would seem realistic if Orcus could kill my Level 1 Fighter with the first blow, even if my Fighter would still have 7 HP remaining.

Are there any similar rules to standard use cases?

Thanks!

Answer 1

4e has no "massive damage" rule.

The rule you referenced is only applied when making a Coup de Grace attack, which requires the target to be helpless. Unlike many other editions of D&D, the 4th edition has no rules that would cause a creature in standard combat (as opposed to special circumstances, such as being helpless) to risk instant death from an attack that deals a large amount of damage but does not reduce the creature to zero hit points.

A group could, of course, introduce such a house rule for this purpose if they so wanted; nobody is going to kick down your door and arrest you for modifying the rules. However, it's important to remember that the rules were written by professionals who would have included such a rule if they thought it would improve most groups' play experience. Much like an automobile engine, tinkering with RPG rules is likely to end in problems if you don't know what you're doing. Off the top of my head, I can think of several ways adding such a rule would influence the game, some of them beneficial and some of them not. In particular, it's worth noting that later 4e publications (generally from MM3 onwards) opted to give foes higher damage and less health, to speed up combat; this increases the likelihood that rule will trigger for both sides compared to what you might be expecting from looking at earlier books.

What are "hit points" anyway?

There are two aspects to most roleplaying games: rules ("crunch") and fiction ("fluff"). When Bob describes his character, Grognar the barbarian, swinging an axe at a nimble pixie, that's in the fiction. That description is then translated down into the rules as an attack, which is resolved, and the result is then translated back up into the fiction. So what does it mean in the fiction that a 7' tall half-orc "hit" a 1' tall pixie with a huge axe and did 16 damage out of its total 58 HP?

From the PHB, p293 (emphasis mine):

Over the course of a battle, you take damage from attacks. Hit points (hp) measure your ability to stand up to punishment, turn deadly strikes into glancing blows, and stay on your feet throughout a battle. Hit points represent more than physical endurance. They represent your character’s skill, luck, and resolve—all the factors that combine to help you stay alive in a combat situation.

This is hugely important. When an attack deals hit point damage, that does not automatically mean it dealt physical damage to the target; it reduced the target's ability to stay in the fight.

For a creature like a troll, which relies on being big and tough and regenerating, that damage may very well be represented in the fiction by actual physical wounds. On the other hand, a high-level rogue could have several times as many hit points as that troll, but would die from even 10% of the physical wounds it would take to incapacitate the troll. Her hit points are instead more likely to represent the ability to throw herself out of the way of attacks. An attack that deals no damage to her is one that's easy to avoid, while one that deals hit point damage is effectively forcing her to really exert herself to dodge it. Eventually, she'll run out of the stamina/endurance needed to keep making those incredible dodges and a blow will reduce her to 0 HP, which would translate into the fiction of actually finally physically hitting her. And like most humans, one good, solid blow with a sword is enough to incapacitate her.

This separation between "hit point damage" and "physical damage" is why non-magical means like taking a short rest or being shouted at (encouragingly) by a warlord can restore hit points, even though they couldn't do much about physical wounds.

What, then, would a house rule that causes a target struck for a large amount of HP damage to risk instant death represent in the fiction?

Answer 2

It only applies to helpless targets, and for a good reason.

That reason is that all a coup de grace does is compare critical hit damage from an attack to your bloodied value. If critical hit damage is enough to take you from fresh to bloodied, it will kill you as part of a coup de grace, which can actually be performed in combat as a standard action, explicitly against a helpless target. (Rules Compendium, p.241)

If taking this much damage was a danger to instantly kill a non-helpless target, then there'd be this danger of being instantly killed whenever you took a critical hit from anything that could successfully coup de grace you. And that's a decent number of monsters, especially if you're using the later monster maths from Monster Manual 3 or the Monster Vault that made monsters deadlier but less resilient to pick up the pace of combat. As a low-probability event, a critical hit is especially dangerous to assign significant benefits to, because only PC attack rolls have enough of a long run to average out in. A needlefang drake swarm might not even get to attack ten times, total, ever, but if two of those happen to be critical hits that kill PCs outright, that hugely disadvantages the party compared to any two other rolls.

A side note: for a level 1 Fighter, Orcus (level 30 solo brute) is an outside context problem.

It's not an uncommon mindset, on approaching an RPG with detailed rules for tactical combat, that the "RPG world" is actually constantly operating under those detailed rules, and anyone can demand they be strictly enforced at any time by rolling for initiative. This mindset is going to backfire spectacularly on you in 4E, not least because Orcus's statblock for combat isn't intended to represent the entirety of Orcus, just the part of him that would surface during a tough fight with a worthy adversary. It's why the DM's guide cautions you against using monsters more than five levels distant from the PCs in either direction - what's going to happen is much more of a foregone conclusion, and the simulation starts breaking down.

You know what's going to happen if a level 1 fighter and Orcus collide. Running it on a tactical map isn't going to tell you anything new about that fight, even if technically the level 1 fighter might not die outright to a single blow from Orcus but instead when they get scourged at start of turn by the damage aura. Orcus (level 30 solo brute) is there to be a challenging confrontation, alongside whatever else he might bring, for a full party of PCs near or at the peaks of their power. It's unrealistic to suppose a level 1 fighter falls into that category.

Orcus or Orcus accessories might be involved with much earlier characters, but not on a tactical combat perspective as a fair fight. Paragon-tier characters on a mission into the Elemental Chaos might be fighting around the edges of a battle with Orcus at its center, and random collateral damage from Orcus can be an on-level obstacle for them, a level 18 hazard. A heroic-tier fighter might be escaping from a ritual Orcus cultists are enacting to destroy their humble peasant village, but eluding the shadows of Orcus and the collateral destruction can just be a heroic skill challenge and doesn't have to involve the tactical map at all.