Hand Crossbows and Ranger Woodchippers in 5e?

Question

Mikhael is a level 4 human ranger, variant human, Sharpshooter and Crossbow Expert feat. Dexterity score of 16. Archery Fighting Style. Hunter Archetype. Horde Breaker chosen at level 3.

He encounters a pack of 8 orcs, 60 feet away from himself. This is a challenge rating 4 encounter meant for a party of 3-4 adventurers. He triggers the orcs, and initiative is rolled.

Mikhael wins initiative, goes first. -5 penalty on the attack roll +10 to the attack’s damage. Hits. (After all modifiers accounted for, he has a +2 bonus to attack the AC 13 orc) He has a +10 to the damage roll, adds his +3 dexterity modifier, rolls the hand crossbow’s damage of 1d6.

Total damage is 15 piercing. This is the orc’s health, so he dies.

Uses bonus action to attack again with a hand crossbow he is holding.

Orc is 5 feet from the another orc. -5/+10 again, and he hits. Rolls 1d6+13 and gets a 4, dealing 17 damage and slaying the orc.

Because he made a weapon attack, he can make another attack with the same weapon against a different creature that is within 5 feet of the original target and within range of his weapon. -5/+10 but dice are good, he hits. Rolls his 1d6+13, gets a 3 on the damage roll, slays the orc.

The remaining orcs then spend their turn becoming no longer surprised.

The ranger moves 15 feet, bringing an orc on the outskirts of the group that was previously too far away into his long range ... rolls without disadvantage ... -5 / +10. 15 damage which kills the orc. Then, because he used the Attack action and attacked with a one-handed weapon ... hits. using bonus action to attack with a hand crossbow. Hits again, 15 damage and slaying the orc. The orc was standing within 5 feet of another one, so because he made a weapon attack, he can make another attack with the same weapon against a different creature that is within 5 feet of the original target and within range of his weapon. hits, dealing 18 damage and slaying the orc.

The two orcs, aggressive as ever, use a bonus action to reach 15 feet away from the ranger and then finally move 15 feet to enter melee range. Both bring their greataxes to bear, dealing 18 damage to him. The ranger, who has a minimum of 25 hit points at this level, still retains (at minimum) 7 hit points, survives. It is now his turn.

He turns his crossbow on one of the two orcs and, because being within 5 feet of a hostile creature doesn’t impose disadvantage on his ranged attack rolls, he attacks the first orc. hits. -5/+10. 16 damage, slaying the orc. He then turns to the next orc, using bonus action to make an attack -5/ +10. 15 damage because of it. He slays the last orc.

Everything here is accurate according to the rules.

This is an extreme example, but the crunch is this: the Crossbow Expert feat and Sharpshooter feat are easily exploitable in this manner with little else, and the penalties for extra damage are... Kind of minimal. So... How do you, as a DM, deal with this cheese and cheese like this without outright going "no, you can't do that"?

Do you sculpt combat around them to the detriment of other characters? Do you talk with them about it, and, assuming they're willing to talk it out, how do you remove this sort of business? Should you just accept it?

Answer 1

The PHB errata v1.0 says this on the Ammunition property of weapons:

Loading a one-handed weapon requires a free hand.

So while the ranger could start a fight with two loaded crossbows, he would need to drop or holster one to reload the other. How to best juggle two crossbows within the action economy is not a trivial question and if you start thinking you will soon see the constraints.

While these make your exact scenario unfeasible, since the whole fight is rather short, he could opt to drop one of his crossbows after firing it in the first turn and draw a one-handed melee weapon when the orcs reach him. While this would not be as impressive as what you describe, it is still fairly effective. But do not forget that the ranger has started with serious advantages: he is specialized in ranged combat and has surprised a group of foes without ranged weapons from a distance. Do not be surprised that he made short work of them.

Please note that creature CR and the encounter difficulty calculated from them is a benchmark only. The exact situation and composition of the opposing forces can produce great sway in the actual difficulty. Some such stituations are listed in the DMG on pages 83 (party size) and 85 (environment and setup).

Answer 2

Epic Characters

These games are about epic characters, and as such there will be some of what you call "cheese" when the dice land right. Some combinations do have more cheese in them than others.

Consider a Tiefling Warlock with his Infernal Legacy and Devil Sight laying down magical darkness only he can see through and them spamming EB+AB+RB to keep the enemies contained his bubble of death.

Consider a Paladin Rogue, Divine Smite + Searing Smite + Sneak Attack = huge damage spike that might take down a boss level monster in one hit.

Probabilities

What you are calling cheese though, is playing their character. There are real risks, and you're ignoring the probabilities. You while you think "the penalties for extra damage are... Kind of minimal." means you haven't done the math.

So, what are your chances of hitting an AC 13 with +3 modifier and a -5 penalty on a d20?

Well, to keep math simple we'll ignore the rounding, and assume 10 is 50% chance on a natural roll. On a 20 sided each +/-1 is +/-5% chance to hit.

So, let's say 13 AC on a natural roll would thus have a probability to hit 50%-(3*5%) = 30% of the time.

With a +3 modifier, a +2 proficency bonus, the +2 from archery fighting style, and the -5 penalty, you get 30%-(5%*2)) = 40% chance to hit each time. Without Sharpshooter, the probability for each shot to hit is 30%+((5*7)) = 65%.

That means of the 9 attacks your ranger made, there would have a statistical expectation of landing about 4 (3.6) attacks. Where a shot without sharpshooter would have an expectation of hitting about 6 (5.85) of them. So, the question that the ranger has to really ask himself is if the damage lost from missing those two shots are made up by the damage of hitting them.

Also, the feats aren't free. The match above is ignoring the real opportunity cost of the feats. Let's say they took only Crossbow Expert at the start and took ASI as +2 to dex. Adding 2 to the dex skill and +1 to the modifier, would be another 5% to the chance to hit, and 1 more damage on each arrow. Bringing total chance to hit up to 70%, the expectation to be hitting 7 of the 9 orcs, and the damage to be 1d6+4. That means you hit 3 more orcs and every orc you hit deals +1 more damage.

Conclusion

All that said, the average DPR of sharpshooter, even factoring the increase misses, is better. I do think it is a powerful feat, but then, so are a lot of the other feats. It still isn't capable of doing what the question says, but doing the math on it, I know I'm itching to make a sharpshooting crossbow expert Ranger now.