You say "but isn't that cheating? No." but my immediate, visceral response is "YES...."
[snip]
But for people who look to things like CR, XP budget, etc. as meaningful guidelines...for people who lack the time, patience, and mechanical experience to constantly craft their own opponents...a lot of your other solutions aren't especially helpful. And constantly changing the mechanics as a fight goes? Well...there are some DMs who consider that an unacceptable form of behavior on their part, even a violation of trust between player and DM.
I don't really want to get bogged down in the first part of the response, which is a philosophical debate with no objectively correct answer.
In my opinion, D&D isn't a competitive sport. It's a past-time to be enjoyed by friends. It's not poker (or even Settlers of Catan), where you can run multiple games per night. A D&D campaign could involve the investment of 200 hours or more into a single character. If the DM applies the rules rigidly with no flex under any circumstance, that investment (and the associated "fun") can be wiped out with unlucky rolls despite the best efforts and ideas of the party.
I'm not advising the DM flex the rules every few minutes, or ignore the dice completely. That seems to be a very black-or-white view to me. I'm saying there's a touch of grey. You don't flex the rules if it's obvious to the players. I don't rule one way on
fireball this week, and another way next week. I don't reveal the monsters hp at the start of the battle (hence, I can change it during the battle if I need to). I don't roll a 16 and then call it a 12. I agree that no player would enjoy a campaign where they can
see the DM "cheating". But, likewise, if the DM's only job is to apply the rules rigidly, they can be replaced by a computer. There's no human element.
Anyway,
that's my opinion. I also respect your opinion as an equally valid approach. I'm confident neither of us will convince the other as to the rightness of our position. On my part, I've been DM'ing successfully using my method for 30 years with two large groups who are very happy with it. My players' enjoyment would be diminished if I didn't sometimes reduce the starting hp of monsters in secret if they were struggling, or add a complication if they were finding it too easy. But I can absolutely see how other groups would find that unacceptable. The beauty of the game is that we can each choose a method that works best for our own circle of friends. So: we're both 100% right, and we both love the game. Good outcome.
...
What I do want to discuss, though, is the use of CR and XP as meaningful guidelines. My question is: for who? D&D is an inclusive game that should be catering to all player types. Sure, there are a lot of us with decades of experience and a love of optimizing characters. There are also vast numbers of players who are young, or are semi-involved partners (boyfriends, girlfriends, husbands, wives, etc), or who only game occasionally, or who do it for purely roleplaying purposes (sub-optimal builds).
For many of those players, a solar is going to be terrifically difficult even at 17th level. I've seen a "non expert" player attempt to wrestle an ogre at 7th level, fail dismally over multiple rounds, and take terrible damage... when tactically, he could have mangled it in a couple rounds with straight weapon attacks. He had no idea of its hp, or the best tactical option. He was simply having fun.
This issue is magnified at high levels. High level D&D characters are hard to play, and the monsters they face are complex. Not every DM is an expert, either. Running a long (multiple round) combat with 17th-20th level combatants is something you learn how to do over many years.
Finally, there's simply no way you can account for every possible combo of player abilities. Your boss monster needs to be able to handle save-or-die spells... mass damage from the party of 4 barbarians/fighters/rogues... stun-locks... flying or invisible PCs... mass summoned creatures... PCs with endless slots to burn on
counterspell. If every boss can handle all of those things equally, where's the diversity? A tarrasque can't handle flying PCs, and a solar apparently is vulnerable to a
feeblemind. Good to know. That doesn't mean their CR is wrong, on average. It means that particular creature was vulnerable to a tactic that your particular party employed. If you want to change up the difficulty level, use different creatures (if you're unwilling to fudge it on the fly).
That's not the fault of WotC. There is
no possible way they can guarantee accurate CRs for every playing group in the world. That's not even possible if every group in the world had exactly 4 players and they each played a fighter, cleric, rogue and wizard. There will be different levels of tactical awareness, player experience, DM style. For example, I play dragons with absolute tactical ruthlessness: stay in the air, focus fire, coup de grace a fallen foe to prevent him getting healed back to consciousness, use terrain effects and allies to maximum effectiveness. A dragon played by myself as a DM will be vastly different to a dragon played by a newbie DM.
The original complaint was implying that the solar was a pushover, and hence the CRs are too easy for a proficient group. That, in my opinion, is a good thing. The game should err on the side of "easy" rather than "hard".
An experienced group usually has an experienced DM, who knows all the tricks for increasing difficulty. Add more encounters per day. Deny short or long rests (the monsters attack the PCs while they're in camp, repeatedly, or they're in a hostile environment which prevents resting). Add more creatures to an encounter. Use creatures that you know will target party weaknesses. "Cheat" (i.e. add legendary resistance, or more hp, or whatever, to extend the battle to a satisfying dramatic length that suits the story). Whatever works.
For those DMs who lack the time, patience and experience to use the tools... well, I just don't buy it. The tools are simple. None of the items listed above are harder than what the OP is already doing: DM'ing and adjudicating for a group of 17th level (!!!) characters.
The OP is asking for WotC to design a CR/XP system which works perfectly for one single group in the entire world (3 players, a warlock with save-or-die spells, and a DM who doesn't know what to do story-wise with a solar who fails a saving throw). That's a pretty niche group. Or maybe WotC should design a CR system that accounts for every possible group?
The CR of a solar is 21. But add +1 for each PC less than 4. Add another +2 if the DM is very experienced and applies optimal tactics. But deduct -1 if the DM is a newbie. Deduct another -3 if the party has multiple save-or-die spells targeting Charisma. Also deduct -1 if the party is all barbarians with magical weapons.
That seems a lot more complex than just telling the DM: yep, the solar died. The players had fun; nobody died. Make it tougher for them next time by using a boss with legendary resistance and some minions.
