I enjoy running D&D and have a few games going every week, but for me, the DM, I find combat to be the most tedious and uninteresting part of the game. I look forward to leading my groups through their journeys all week long, but in a session with any combat it will be two of the three hours we play having them fight whatever it is they need to deal with. Most of the time its obvious they’ll win (I’m not -trying- to tpk them), so.. I’m bored. The outcome isn’t interesting.
To be clear, my players say they enjoy the combat I run, and they are asking me for even more. It’s me who doesn’t enjoy it, and while I don’t want to be rid of it entirely, I really don’t want to spend most of a game I’ve been looking forward to all week with people whittling down monsters till they flee or die. There just isn’t any story there, other than ‘there was a skirmish, and some of you took injuries and were knocked unconscious). Obviously, some fights are very story focused as the outcomes will affect how the world reacts, but those scenes are the exception, not the rule. 

As for my question - I know that maybe D&D isn’t for everyone, and I can accept that. Can anyone recommend another TTRPG where conflict and danger is resolved much faster?
Alternatively, can anyone see a homebrew rule working where all damage from players and monsters is tripled to make it faster snd deadlier (and honestly.. more realistic?).

I’d prefer to stay in D&D since I guess you could say I’m invested in it now, and its very well supported, but spending 2 thirds of a game session feeling like I’m just going through the motions isn’t cutting it for me anymore. 

It's a real easy homebrew tweak to cut the HP of literally everything in half.  Did you have 60?  Now you have 30.  It can be harder on DDB, but if that's the case you could simply double the damage everything takes.

The worries you'll have are that certain big-punch monster abilities, like a dragon's breath weapon or a spellcaster's AoE blasts, are tuned to be extremely damaging already.  Double the damage of a breath weapon and the only reason you try to make your save is avoiding instant death from Massive Damage rules.  You may want to exempt such big-blast abilities, both enemy and PC, from whatever scaling you use and instead choose to double the damage of 'normal' attacks.

Alternatively, you may want to look up the 'Minion' rules from 4e and redux them.  Essentially, 'minions' are incomplete(ish) monsters meant solely to make a fight with a larger, more primo critter more hectic/dangerous.  Minions only ever have one hit point, they only ever have one action (their basic attack) and they never roll for damage - if they hit, they deal a fixed amount of damage.  If something forces a minion to make a save against half damage, they take none instead if they make the save, but otherwise any PC can kill a minion with a single solid blow, as any hero should be able to, while allowing minions to be an ongoing battlefield hazard - or a resource a particularly evil master can consume for certain abilities.

There was a game called burning wheel I loved playing, complex, but it was fun. But it’s combat was actually worse than D&D. To the point of my group doing everything we could to avoid it. But the role play and character advancement (no class or level, just skill that went up as you used them more.) was really fun. So if you’re looking for a very complicated, rp heavy, combat light system, it can be fun. 

Have you tried introducing other obstacles to make it more interesting? For example, what about terrain challenges? Something that needs to be completed during the combat?

If you're concerned with speed of combat, I would focus on one big monster so that you don't have to worry about lots of individual damage roll tedium.

You can also ignore the hit points of the monsters entirely- improvise as you go and have them die when you feel like they should. This could also be done with damage amounts and even attack rolls. Kind of an extreme version of fudging dice, but it might help.

You might consider turning some combat encounters into skill challenges. Use sides initiative and present obstacles for them to overcome as a group. They'd have access to their normal combat abilities as well as creative problem solving using skill checks and items in their inventory. The outcome of those interventions (based on DCs you set or benchmarks you institute) would then impact what consequences follow. 

An example: My party was trying to retreat from a failed dungeon incursion and the baddies were swarming us. We ran into an elevator room and shut the door behind us. A skill challenge ensued. Every round until the elevator came, we had to work together to hold the door until we could leave. Sometimes, the door opened a little and we got hit with weapon or spell attacks. Sometimes, we used crowbars to wedge it shut (improving our athletics checks to hold the line) or did structural damage to make it harder on them to get us (helpful but risky to us from flying debris). Sometimes we healed each other. It was tense, it was creative, and it was collaborative. One of the most memorable combats of my career. I've since used this mechanic a few times in my own campaign to the great enjoyment of my players. 

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And other similar ways to make monsters be interesting, clever and real even in combat might help.

Alternatively you could try another game system where combat is more nuanced.  I play GURPS and you could try the fretastes. (GURPS lite) and see if it's to your tastes.

Quote from theologyofbagels >>

You might consider turning some combat encounters into skill challenges. Use sides initiative and present obstacles for them to overcome as a group. They'd have access to their normal combat abilities as well as creative problem solving using skill checks and items in their inventory. The outcome of those interventions (based on DCs you set or benchmarks you institute) would then impact what consequences follow. 

I second this option. The few times I have seen it being used have always been more interesting than "hit the thing until it dies". Gonna try to introduce my group to it once it is my turn to DM.

Not quite an easier combat system, but The Witcher TTRPG has damage modifiers for where you hit a creature in combat. So hitting an arm only does, like, half damage but a head shot would end up tripling the damage. It could be something to consider, numbers-wise.

Another thing (which my DM introduced to our home games) would be to have more fight mechanics, instead of just going into initiative and slogging through combat. Now my DM pulls a lot of inspiration from World of Warcraft, but there are plenty of games that utilize fight mechanics. I mean, even D&D does. Just look at lair actions. It's not something that has to be reserved for the Big Baddies, and it doesn't have to be part of every fight. But a little here and there to spice things up for you, mainly, as well as your players.

Alien rpg is worth looking into. It's simple and the combat can be insanely fast. But the game is in itself a lot of roll playing, then skill checks, then more story and roll playing. 

Then.. well then there is the everyone running and screaming part with people dying. 

What levels are your games playing at? High levels? Low levels? Are you running Homebrew or published adventures? Just curious.

You say combat is two out of the three hours you play. How many combats are you talking about? One per session? Three? I ask, because if you are running several combats, which go by fairly quick, then you are already better off than one big combat that takes most of the gameplay.

If it's fairly short combats, but several per session, then maybe you can lean more into some Roleplay aspects of the game. The game I'm in, combat is a good portion of the game, but we've also had a few 4 hour sessions go by with not a single combat those sessions. This might be harder if you are running a published adventure. Or some of the other suggestions above, like skill challenges, could be good options. There was an old module for AD&D I DM'd, The Lost Tomb of Martek, that had a thing where another group of adventurers stole an important item from us. At one point, we were chasing them, but because of the area we were in, distance warped, so each round a die was rolled and sometimes we were right behind them, then far apart. I don't remember all the details, I wish I kept the module, but it was different and it was fun. EDIT: Make more use of the Social and Exploration pillars of the game. Puzzles, Traps, mysterious glowing orbs that power the barrier that keeps the party from the next combat/area of the dungeon, that the players have to figure out to progress can keep the players engaged while limiting your boredom with combat. 

If it's long combats that seem to go on and on, then as Yurei pointed out, HP can be a problem. Cut HP and increase damage is an option. Players and monsters. If you " really don’t want to spend most of a game I’ve been looking forward to all week with people whittling down monsters till they flee or die."  being able to take out monsters in just a few rounds, and the monsters being able to take out players in a few rounds might make the combats less boring and more tense/deadly. We didn't have a coin with "Killer Dungeon Master" on one side and "DM's Grace" on the other, at our AD&D table, for nothing :) Some might disagree, but there is nothing wrong with a PC death to remind the players that combat has consequences. It should be rare, but not nonexistent. Maybe they would like to try out RPing an encounter instead of just whipping out their swords and settling it the Murder Hobo way. (I'm not implying your players are Murder Hobos, it was just my attempt at humor)

Also, for obnoxiously long combats:

1. Use timers so the players have to decide quickly what they are going to do each round.

2. Roll group initiative instead of individual. Monsters go, then Players go. Or Vice Versa, which ever won initiative. Straight up d20 roll (or a d6). So who goes first when it's the players turn? See #1, tick tock, tick tock. They'll figure it out, eventually.

3. Roll to hit and damage at the same time, Monsters use average damage on their stat block instead of rolling for damage.

4. Just make it so monsters can only take X number of hits to die instead of HP and doing all that maths. Nonimportant monsters maybe 1-3 hits, and they die. Important Monsters (or the big encounter of the night) 4-6 hits, maybe more depending on how the night is going. BBEG? Just do the math on that big old HP pool, they're the BBEG and deserve the courtesy.

Other games I've played don't focus on combat much at all, and combat is much deadlier as a result because you're never godlike at it and your HP never really changes outside of very expensive augmentations.

Traveller and Call of Cthulhu (iirc) have it so that it's (iirc for CoC) your strength + your size = your HP? For traveller 2e mongoose it's that you initially take damage to your endurance score, then either your dex or strength score (player's choice), once 2 of your scores drop to 0 you die. Traveller is a 2d6 system and the highest score an unaugmented human is 15. So sh**'s pretty deadly, as your scores don't really change much at all.

So here are some more "drastic" rules changes that could completely change the feel of the game:

1. All PCs only get their level 1 HP, it doesn't increase when you level. Obviously if their con mod changes this will be the only way to increase your HP (outside of the tough feat).
2. Make damage go to their ability scores instead of to HP

You may think "My players will instantly die to anything! This is crazy!" that is the point. In stuff such as Traveller, CoC, etc, a knife is still just as deadly to you at the beginning of the campaign as it is at the end of the campaign (when you're unarmored that is lol, a knife ain't gonna do sh** to someone in a battle dress).

Some not so drastic options:

1. Give monsters abilities that aren't just "I attack". Air Elemental? Their whirlwind is just a thing that happens within 10 ft of it. This new monster takes away your highest level spell slot when it hits you. Save or die effects (use sparingly). Add stuff that isn't just attacking so that the monsters make the combat more interesting for you on their own.
2. As suggested, use timers.
3. Use digital dice rollers and combat trackers. I play on roll20 and so all that is taken care of for me (use the Beyond20 extension to roll off your DDB sheet and hyave all the rolls show up in the r20 chat). This makes stuff way faster as it cuts down on rolling time and you have the initiative always there.
4. Roll a bunch of d20 rolls on your off time, write them all down. Use these as your base rolls for your combats and cross off your used one and move on to the next. Roll like 80 and you'll be good for like ~5 sessions depending on how many combats you have.

That's a lot of time for one fight. Are your players taking forever to decide? Could be that they're scared of the consequences of making a misplay. If so, increasing enemy damage would make this even worse! Are they taking forever to parse their own features? Maybe they're playing at too high a level. You get more and more options each time you level up. High level combat can take ages, especially if players aren't already familiar with most of their kit.

I find that my combat goes the slowest when players are drawing out and measuring areas and distances on a grid. They do this because half of them are wargamers. I wish they wouldn't, but I don't know how to break them of it.

Find ways to speed up combat.  I think everyone would get bored with combat being that long.  How big is your party?  

Ways to decrease combat time:

• Incentivize using approaches other than combat.
• Instead of many enemies, use fewer more powerful ones. 
• Cut table talk out.  No more, "hey if you move over there I can sneak attack and it will let that guy fireball" stuff.  Consider limiting things character tell each other to like one sentence.  Treat it like you're fighting in real time.  Maybe even set timers on a player turn, as an experiment.  
• Cut out unrelated conversations while gaming.
• No phones or computers at the table for players.  Maybe controversial as a lot of people use phones or computers for various things like dice rolling but honestly I think harms more than it helps.  Phones I can tolerate as long as players stay off if not dnd related.  As combat drags and time between turns increases, people start doing other things on their computer or phone and that slows things down further.  Computers also create a physical barrier between everyone at the table that makes it feel like everyone is playing a video game separately instead of playing a live game.
• Use tools on the internet (only DM).  The combat tracker here on DNDB is actually pretty good if you own the content here.  

Those are just a few off the top of my head.

Thanks for all the responses, everyone! It's given me a lot more possible solutions to my problem than I expected, and I'll probably have a discussion with my players to see what they think too. Like most issues, this one is multi-layered, and I think that several fixes are needed. 

Just to answer some of the questions and give more context, as of right now I'm running three separate groups through weekly occurring games of Icewind Dale: Rime of the Frostmaiden (yeah, I know.. but if you've prepped and memoried it you might as well make the most of it). My groups have about 4 people in each one, and we play remotely using discord, owlbear rodeo, and of course, DDB. The group with the most progress is currently level 5 (they're about to start chapter 3/4), and we've been playing for about a year and a half (which I feel is significantly slower than the average). I couldn't say what I'm doing differently to other DMs, since.. I'm never really a player. As per the OP, I have mostly attributed the long game length to combat time, which is why I'm more focused on that.

When combat does crop up it'll usually only be once or twice. I try to design my encounters with the philosophy that all combat should either contribute to the story, or if it's a completely random encounter, should be novel in a way they haven't seen before (obstacles, environmental hazards, etc). Again, my players have told me they really enjoy these scenes and want more, but my issue is how long they take.

My players do take a really long time to decide what they want to do, which I've been working on for some time already (reminding people of turn orders while they're waiting, jump starting each players turn with a very curt 'this just happened since your last turn - what do you do?!', trying to get them into the habits of knowing the details of their abilities, and by moving over to 'theatre of the mind' whenever possible).

I'll try some of these suggestions out, and give my impressions to help anyone else with the same problem.

Edit: Please ignore the RotFM part, I forgot how chapter 3 was structured to be concurrent with chapter 2, the party should be L5 about to level up to L6, so I'm wrong. I don't get why they didn't just fold chapter 3 into chapter 2 since they both form part of the same section of the story.

I'm running RotFM myself, and either you're using idiosyncratic terminology, or something is off? You're supposed to be L4 at the end of chapter 1, when you've done 5 of the Ten Cities quests (plus possibly a starter quest which doesn't affect levelling). Halfway through chapter 2 is when you hit L5 after the first 2 quests. So, how is your party only L5 in chapter 3/4?

Are you doing XP levelling? Be aware that the adventure scales difficulty according to the milestone level and not necessarily XP gained level. I haven't done the maths, but I think the suggested milestone levelling is faster than the XP gained would suggest, which means your enemies are scaling faster than your party. This could be the cause of the slowness of your parties - they've realised that they're outgunned and so are becoming more and more cautious as they realise that a misstep could be fatal. Maybe that's your issue.

Maybe you mean quests by chapters, but that would lead to the opposite problem - your L5 party would be fighting enemies designed to challenge a party of at most L3, so should be a cakewalk, and it really shouldn't take 75ish sessions to do 3/4 quests (we've been doing about 1 quest per 2 hour(ish) session so far, and just finished chapter 1), plus I'm not sure how your party would L5 so quickly. I'm not sure what else you'd be calling chapters, though. I'll leave it there until you give more information on where it actually is (if you want to), but I have to wonder if the problem is that you've not been levelling your party as fast as the adventure expects you to.

Something that I've found help is using physical representations for combat. I used to do theatre of mind (like you seem to), abut one of the problems isnthat you have to keep redescribing the situation, they have to keep rebuilding their image of the scene, and that all slows things down because they're spending cognitive load on imagining what I'm describing, asking what they can see, trying trying figure out what their options are, etc. We invested in a pair of battle mats (basically a sheet of coloured material with a plastic covering that you can use whiteboard markers on and a grid) that I draw the battle area onto. We also have a  of of little coloured stands and bits of plastic that function like a whiteboard. We write the names of the combatants on those to represent them. The advantage is that players can easily see what's happening, we're not spending 30 seconds reestabilishing the scene at the beginning of every turn, it's easier to spot possibilities, and people can focus more on what their next turn will be. That sped things up considerably.

That's a cheap solution that keeps us happy. If you want to spend more on miniatures and/or 3D printing, then you can. That would be much quicker in set up (once the models are made/bought) because you don't have to spend so long writing up their names etc, but obviously a bit of a sinkhole for money - especially if you're considering leaving D&D. My version wasn't to bad, the costly thing was the battle mats.

I know you've edited that you made an error in the pacing of it, but just explain how things have gone (or how I've run it), avoiding any meaningful spoilers.

My 'furthest ahead' group has done every quest in the first chapter, a few locations from the second chapter, and a few homebrewed side quests which arose from random encounters. I never actually intended for them to do every single quest in Ch 1., but after they discovered the hook that would lead into Ch 3. quite early in the game, they took it upon themselves to have a meeting with every single leader of every town to rally them together. It was actually a really great way to have them organically self motivate into going to all the locations, so I barely needed to do any work into motivating them at all.

I've deliberately withheld a number of locations from Ch 2., as I'm going to use them later between the later chapters as a way of giving them more choices and making it less linear. For example, the important NPC that sends them on their way to Ch 5. -isn't- going to know what they need to access the place they need to go in Ch. 6, but will tell them of two places they could go to find out (sorry if this is too vague/not vague enough).

As far as how the pacing of my groups so, they seem to knock over one of the quests in about three sessions (which typically go for about three hours). This is from beginning till the final conclusion. I'm still not sure why we take so long, as the time always seems to fly by. I am using milestone leveling, and I've been sticking to the guidelines in the book (they were level 4 for a very very long time). Now they're level 5 I'm excited (actually, I'm extremely worried for them) about starting chapters 3/4.

Anyway, I know this is all pretty far off the OP I made, but just some insight.

As far as giving them some physical representation goes, my rule of thumb is 'if the combat isn't very tactical' (i.e. fighting a single/two opponent(s) in a room) I'll stick to theatre of the mind to avoid the distractions of a map, and needless pedantic finessing of positioning. If there is complex elevations, or narrow spaces, or just a lot of enemies, I'll switch to owlbear rodeo for something a bit more war gamey.

Sounds to me like you're doing just about everything you can. Part of it might be boring you because you're running the same encounters 3 times, though. ;)

Despite what the marketing wants you to think, D&D isn't everybody's cup of tea. I wonder how much of the adventure could be easily refitted for a different game... Particularly one centered on survival mechanics like Ultraviolet Grasslands or something. Though players might hate losing the mechanical specificity of their 5e character builds.

Most of the time its obvious they’ll win (I’m not -trying- to tpk them), so.. I’m bored. The outcome isn’t interesting.

This part jumped out at me. If the only question in a conflict is if they'll win, then yeah of course it's going to be boring. Even if you speed it up. A more interesting question to pose is how they'll win.

It takes a little more work, but try running a few combats that are more open-ended and see how you like it. Have different goals than just "reduce the enemy to 0 hp." Maybe you need to capture the enemy, and they have regeneration so just knocking them to 0 with nonlethal damage isn't going to work. Maybe the party just needs to get to the other side of the map - or to get the escorted wagon across the map. Set up obstacles where even you aren't sure what the solution will be and throw them in the middle of a fight.

When I stopped approaching every combat's primary goal as "kill everything," my party immediately began trying other things. They made alliances, they took prisoners. Sometimes they skipped by the fight entirely, and a couple times they had to retreat. When the how is no longer a given, the outcome is a lot more interesting and combat becomes a huge source of roleplaying.

To be honest, the problem is that you're spending 27 hours (assuming that the example you gave was typical and average) doing something that would normally take me 2 (maybe 3), which I think it's designed for. That would have me getting tired and burned out as well. I'd recommend doing different campaigns next time if you're doing multiple at a time. Having new fights and new interactions will make it easier. Unfortunately, the horse has already left the barn at this point with that.

It's hard to gauge what it is that is taking 9 hours to do a quest, because we're not there. It could be your style (quite possible, you are the common denominator there), or it could be the players, or some interaction between the two factors, or something else. 

Maybe what you can do is time your combats. Time how long each player is taking for their turn, how long you're taking, and seeing what you can cut down on without compromising the quality. Things you can look out for:

- Are you having to repeat yourself frequently?

Explaining a scene takes quite a while. That is a massive time sink if you have to explain the scene 4 times when you could be doing it once. Encourage your players to be attentive at all times and actively engaging with the scene, even during other player's turns.  Ideally, between turns you should merely be confirming that their actions are valid, not describing the scenes. Intend to do a recap at the end of each round and redescribe the updated scene wheb using ToM.

- Are your players ready?

They really should be planning during other player's turns, and ready to go when it comes to theirs. That won't always be the case (if the Wizard who has initiative just before them launches Fireball and kills their intended target, they'll have to rethink), but most of the time they should be ready to go. Be ruthless. If they aren't ready (and they should be, remember there are times where it's reasonable), skip their go. If they don't come up with an action promptly, say their character is in shock (or, depending on your humour, picking their nose) and doesn't do anything. Next player? They'll soon start planning ahead. How you do it and prepwarning is vital, but be harsh. It's a fight, they don't get 3 minutes to prep for each 6 second slot.

On a related note, make sure you're forewarning players. If Player 1 is just finishing up, say "OK, Player 2, you're up! Player 3? You're next, so be ready!" They should have the relevant dice ready to roll.

- Are they talking?

Each round is 6 seconds. They shouldn't be holding war room cabinet meeting. Short expressions only (you decide how short or long), no conversations. If they want to discuss tactics, that's for before the fight starts, not during. I'd say that they get 2 seconds free speech. If they try to overrun, that costs an action. It's upto you whether you extend that rule for when it's not their turn (ie if the Wizard talks to the Fighter about a potential combo while the Paladin takes his go), but conversations shouldn't be happening during that person's turn.

- Have things as prepped as possible. I preroll initiative and HP for my monsters, so all I'm waiting on is their initiative to insert them in, and we're ready to go. That shouldn't take more than 20 seconds. I have cards laid out in front of me with all the stats of each kind of monster, so no having having look it up. I have different coloured dice, and roll multiple at a time if the monster has multiattack or there are multiple monsters in a row. Each colour corresponds to a different attack. If I can, I'll roll the damage dice (each the same colour as their corresponding d20) as well. Then I'm just narrating, no need to wait for my rolls. Try and find time saving devices like that.

- Are the players having too much down time? If they're spending a lot of time doing not much between combat, warn them that they are in an inherently dangerous position, and being out in the open/making noise/making themselves look like soft targets due to fooling around/insert appropriate reason is likely to attract unwanted attention. Then follow through if they don't focus.

You'll have to dial it in to your party's needs. If they're old hats thatnreally should know better, you can really screw in tight. If they're first timers, they'll need to be exempted completely. You'll just have to judge how tight you can run the ship.