Hello, I am a new DM running my first ever adventure. I have played only 5e (for about 5 or 6 months now) and I am going to run my first game as a one shot all day adventure this saturday.
The adventure will be in a dungeon for four level 12 characters, a Gnome Illusion wizard, human Fighter, human Cleric of light and a human arcane trickster rogue.
I have a bunch of rooms some with puzzles, some encounters and some a mixture of both but I find myself unsure on the maths for working out the encounters. I have an example below, the problem with it is that it just feels very weak against four level 12 characters who have all been 'optimised' to survive the adventure.
So for four level twelve adventurers a 4000xp encounter would be easy, 8000 medium, 12000 deadly and 18000 hard.
I have an encounter that has:
4 skeletons (200xp)
4 Zombies (200xp)
2 Winter Wolves (1400XP)
2 Zombie Ogres (900XP)
1 Zombie beholder (1800XP)
The book says to ignore really low rated monsters when working out totals so ignoring the basic zombies and skeletons that works out as 4100xp, with five monsters you multiply that by two making it an encounter of 8200 xp and so of medium difficulty for this group.
That feels a bit generous to me so I would like to ask some more experienced DM's if this sounds right to you, does it seem too easy?
Any advice would be very welcome.
Thanks
Phill
PhillPowell wrote:
A lot of it also depends on terrain and monster tactics. If the party is prevented from getting to the zombie beholder for a number of rounds the eye ray could make the encounter more difficult.
And as FrogReaver wrote, 5e is designed to account for an adventuring day rather than individual encounters, so if this encounter is early in the "day" it will be much easier than if it is later in the "day."
Thanks for the input guys, it has really help me get it more into context 
I love this place!
The 12th level cleric has the Destroy Undead feature, so all CR 2 or lower undead will be destroyed - that takes out the zombies, the skeletons and the zombie ogres in one swoop. The winter wolves and the zombie beholder are left. The 12th level fighter gets 3 attacks per round and will probably have some feat like Great Weapon Master; I would expect him to have 90+ hit points and a solid AC. I suspect he could take out the 2 winter wolves in 2-3 rounds even with them attacking with wolf pack and breath weapons. That leaves the zombie beholder. Let's assume it gets an eye ray off for two rounds (because I doubt it would last that long) - it might, but probably won't - take out one character before it is killed. The cleric then heals that character.
I have played with 8th level characters and been amazed at how powerful they can be. Four 12th level characters like yours would deal with an encounter like the one you describe easily IMO. I take the DMG guidelines very lightly for encounters because they do not seem to take a lot of factors into consideration, such as those FrogReaver raises and those of the class features, feats and the spells the characters have available to them, amongst others.
When you assign the HP totals for the monsters cross reference your value to the table in the DMG for monster design. I've found that the HP totals in the MM to be low in comparison. In addition, I've found that using the HP totals in the table make the combat feel Hard or Deadly when the math indicates it will be Hard or Deadly.
El_Condoro wrote:
I think some of you are missing the point.
There are reasons why it may be easier/harder to deal with 10 monsters, or 4 monsters, or 1 monster; but that is not the issue.
Accoriding to the DMG, it is quite possible that in one day you have 3 different encounters, each one is calculated to be the *exact same* difficulty..... but upon success you will get *drastically* different XP for each of the 3.
The DMG tells you that fighting 10 of MonsterX is *exactly* as difficult as fighting 4 of MonsterY. But killing the 10 X's gives you 1000 XP, and killing the 4 Y gives you 2500xp. (I made up those specific numbers, but the real ones would have a similar issue)
Isnt nit cleric channel divinity on a daily timer?
Rhenny wrote:
FrogReaver wrote:
Coredump00 wrote:
Hello Phill.
Dibs.
The math you have is correct; and remember this is only 1/6 of the total challenge to the party before they reset their powers.
I build my encounters around a short rest after each because that's what my players want - so the encounters are little stiffer than DMG guidelines (about double). The game I play in, the DM lays out the budget based on the entire day (essentially 6 encounters) and divides it up - it results in some tough encounters and some really easy ones. So, there are multiple ways to do it.
My only advice is to make sure that your encounter numbers (in terms of participants) are varied - it makes sense to add a few monsters to 'balance the math' or a bunch of low CR baddies to make the fight seem superficially tougher, but that tactic should be used sparingly to avoid combat bloat. Fighting mobs gets old. If an encounter starts to feel light, that's what "Hey, look who got attracted by the fighting! A wandering monster! It wants to join in!" is for.
El_Condoro wrote:
PhillPowell wrote:
Tony_Vargas wrote:
PhillPowell wrote:
(Continued from last post)
As DM, if I feel as if an encounter is too easy, I will send reinforcements if it fits the story. My advice to you is to keep some foes in your back pocket so you can have them join the fray at a dramatic moment. If you want to increase difficulty have them use ranged attacks while pcs are engaged. They can fire and take full or half cover too. Also, when possible, have reinforcements come from a different direction. If you can engage the pcs on multiple fronts, it becomes much more difficult.
Cheers. It is great that your first session was fun. Keep up the good work.
Rhenny you make an excellent point on perspective. I am suprised how much that thought (as I play twice a week) did not even occur to me...
I will take on your idea of reinforcements too, thank you