User blog:Dragokar62/How To Choose The Right Monster

How To Choose The Right Monster

To me, this is the hardest part of being a Dungeon Master, finding just the right monster for the party to fight. Even if it’s just a simple wilderness encounter, if you choose one that is too easy, the players don’t get much out of it. They look around after the short fight and say ‘well, that was easy’. But then the opposite occurs and they are struggling just to stay alive, looking at you like you’ve betrayed them somehow. There isn’t a single DM I know that hasn’t struggled with this concept, myself included. Over the years, I’ve learned a little more about the mechanics of choosing the right monster for them to fight, and with the 5th Edition Dungeons & Dragons rule set, I’ve found other ways to help find them. Here, I will list some of my observations and tips that I use to find just the right monster for your party to do combat with.

There are some charts in Xanathar’s Guide to Everything, where they take the number in the party and match that with a CR for the monster, but in looking at that chart, I’ve seen parties blow through those same CR monsters without a backward glance, but at the same time, I’ve seen parties struggle with them. It’s a good starting point to choose a monster of that CR, but there are other factors that should be taken into account.

We’ll start with hit points. The going trend is to give players maximum hit points instead of making them roll for them. I’m not against this trend, just pointing out that maybe Wizards of the Coast didn’t take this factor into account when they set up that chart. The standard fighter has around 150 hit points at 10th level, but if you take the fighter who has to roll hit points, or take average hit points, that number shrinks to 110 (that factors in a +5 Constitution modifier, if you don’t have one that high, then the numbers are lower). You might not think those 40 hit points make a difference, but they do. That’s almost one-third more than a character would have if they had to roll for hit points. This makes it harder for the monster to kill a single player, let alone an entire party.

The other factor that WotC throws in there is the number in the party. Four, five or even six characters against a single monster. In this day and age of 5th Edition, I’ve noticed that the sheer amount of damage being done by players has risen to amazing proportions, compared to previous additions (except 3rd, which was insane! Don’t believe me, look it up!). A fighter with two attacks with a long sword and a 20 Strength, plus Action Surge can add up fast. Add a rogue and a wizard in there, and you’re looking at around 100 hits of damage in a single round. Unless it’s a damned dragon, they’ll have it dead in two rounds (average of 180 hit points for the monster with a CR 13 (for 5 players) for a 10th level party). The monster is at a serious disadvantage against a 10th level party of four or five, let alone six or higher.

Armor class. It seems that the top AC for a monster of around a CR 13 is 20. That might sound like a lot to most, but when you factor in the fighter with a 20 Strength and a +1 weapon, and a Proficiency Bonus of +4, that 20 isn’t so high. They have a +10 to hit with those numbers, making that 20 AC a 50-50 shot. Gain advantage on the attack and it’s now 75-25 to hit. The monster, again, is at a disadvantage in this. It has four or five characters on it and it can only hit one target, and usually the AC of the party is better than average, too.

So, when I look at that chart that WotC put in Xanathar’s, I don’t take it to heart. A 10th level party can generally handle much more than a CR 13 with five in the party. In fact, I would go three higher than that against them, because I feel they should be challenged. But then you have other factors you need to take note of before settling on that monster. Though we’ve discussed what I feel the party can handle, there are things that tip the scales in the opposite direction and that’s what I’ll talk about now.

How much damage can the monster dish out in a round? Some have some special abilities that can hand the party a good deal of damage, like the red dragon. 24D6 fire damage from a breath weapon is quite a lot. But that’s a high level creature that is considered elite. A CR 13 monster isn’t doing to dish out that much damage in a single shot, but you should still pay close attention to how much they can hand out. If you go too high and they Crit on a roll, you do double maximum damage and that could be a party killer. Now critical hits happen and you can’t do much about them, so don’t take that to the extreme or you might just end up making the fight easy for the players, but look at the average damage the book says they can dish out and figure out how that figures in to the hit points the players have. A good fight against a creature should take around 5 to 7 rounds (my opinion only), so take their average damage and multiply that by 5 to 7 and see where it puts you. If you think the tank can handle it, it might be a good choice for you.

Special abilities also play a factor in choosing the right monster. If your party seems to handle pretty much everything you throw at them, find out that can do some damage they can’t deal well with. Psychic damage comes to mind. This is what makes Mind Flayers so difficult to handle. They have psychic abilities that the party struggles to combat. Monsters that can cast spell like abilities at will are another. But if they have too many of those, or too many resistances or immunities, well, that could spell trouble for the players. Balance those so it’s a tough fight without it being overwhelming.

High armor class. Now with the 5th Edition, they nerfed some of the higher AC monsters and made them easier to hit. I’m against this change, but it is what it is, so I make my own adjustments when I feel the need. But a mid-range party might find it harder to hit an AC 20 and this could spell doom for them. Besides, bad rolls happen. They could be having an off night and the monster is kicking their butts. You can’t plan for this, but it’s something you might have to adjust during the moment to help them from a total party wipe. Know what it takes your players to hit and figure out which AC they can handle without it being too easy.

And lastly, make sure the monster fits the terrain or scenario. I’ve had DM’s do the unthinkable more times than I care to mention and I felt they were just picking a monster so they party could gain XP. Like a dragon in a 50’ x 50’ room. Really? Or a Beholder in the forest. Yeah, not likely. A lich walking through the mountains. Um, liches don’t walk, they teleport. So make sure that the monster fits the area and the scenario or your players are going to know you weren’t prepared.

Ok, those are some of my favorite tips for choosing the right monster to throw at your players. I hope this helps those who might wish to Dungeon Master at some point down the road. Let me know what you think about this article. Was it helpful?