#### Asisreo

##### Patron Badass

So, I see very often DPR, Damage Comparisons, and Health being discussed at-length playing D&D.

Often times, in White-Room theory-crafting scenarios, someone will talk about the damage a character can inflict on a target and compare that damage to the health of said target.

For example, someone could talk about how a single scorching ray kills a goblin because 2d6 = 7 average damage and a goblin's average HP is 7. Therefore, if the ray hits, its essentially a guaranteed kill, right?

But we're forgetting the fact that when average damage = 7, it actually means there's only a 58.33% chance to actually kill that enemy. This is because while 7 is the most likely sum of combinations, it still only accounts for 16.66% of the total possible combinations.

So if you have a 65% chance to-hit a goblin with 2d6 damage, you actually only have a 38% chance of killing the goblin, which is really low if you're taking a whole action. Its possible, but its very low.

Now, reverse that but for HP. Imagine the DM decided he wanted to roll for health but he waited until after the grimlock first takes damage. The damage is rolled and it ends up 11, the DM decides to roll the grimlock's health which is 2d8+2. The damage should kill, right? Well, its actually around 50% as well.

If you combine those two mathematical models, the actual percent chance of certain attacks killing a character with rolled dice becomes much swingier. Of course, most DM's don't roll health for their monsters, but it does lead to interesting probabilities.

I just wanted to discuss exactly how damage can be a misleading factor when talking about damage and its relation to HP.

TL;DR

When average damage = average health, it isn't a guaranteed kill. Its actually roughly a 50% chance to kill. Be considerate of these facts when discussing DPR.

Often times, in White-Room theory-crafting scenarios, someone will talk about the damage a character can inflict on a target and compare that damage to the health of said target.

For example, someone could talk about how a single scorching ray kills a goblin because 2d6 = 7 average damage and a goblin's average HP is 7. Therefore, if the ray hits, its essentially a guaranteed kill, right?

But we're forgetting the fact that when average damage = 7, it actually means there's only a 58.33% chance to actually kill that enemy. This is because while 7 is the most likely sum of combinations, it still only accounts for 16.66% of the total possible combinations.

So if you have a 65% chance to-hit a goblin with 2d6 damage, you actually only have a 38% chance of killing the goblin, which is really low if you're taking a whole action. Its possible, but its very low.

Now, reverse that but for HP. Imagine the DM decided he wanted to roll for health but he waited until after the grimlock first takes damage. The damage is rolled and it ends up 11, the DM decides to roll the grimlock's health which is 2d8+2. The damage should kill, right? Well, its actually around 50% as well.

If you combine those two mathematical models, the actual percent chance of certain attacks killing a character with rolled dice becomes much swingier. Of course, most DM's don't roll health for their monsters, but it does lead to interesting probabilities.

I just wanted to discuss exactly how damage can be a misleading factor when talking about damage and its relation to HP.

TL;DR

When average damage = average health, it isn't a guaranteed kill. Its actually roughly a 50% chance to kill. Be considerate of these facts when discussing DPR.

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