But I'm also in the camp of "Balance cannot be well defined. It can be extremely roughly approximated and that approximation will fail. The true determination of balance comes from playtest"
@TheDragonOfFlame GURPS, the only game that allows you to homebrew something 100 times and still get the same numbers as monsters are just PCs with an extra N
Like CR and magic items rarity and spell damage per level (which they give guidelines on how to calculate all three) are very rough, and, in my experience, are often wrong
@Someone_Evil guidance on balancing that the DMG just plain doesn't offer despite giving you the rundown on what not to forget (of which steps 1, 4, 6 & 20 are totally useless). 3.5 didn't give the basic recipe, so people made up stuff using their best guesstimates. 5e offers a make this rundown without telling you how to do it properly.
@Medix2 Yeah, basically. I do a looot of comparing to other things in the system, making random connections like "30 foot tunneling speed is equal to darkvision + the levitation spell"
I can't help but feel like if there were a more detailed recipe it'd get called out for hamstringing creators too much, but that's probably just me not being familiar with the same things as you, and thus not understanding what you're looking for
@Someone_Evil The Dark Eye has a page in the creature book that points out why you need to be careful when screwing with the monsters and how changing only the statistics of health and damage can make a monster much easier or deadlier. It helps that TDE 4e goes a very simulator approach.
@Someone_Evil That can be a problem with guide rails. People get so used to them, they don't realize when they can snap them off and get greater flexibility or efficiency from their tools.
Going back to a homebrew unkillable pheonix... I can think of at least one situation where I've used essentially unkillable mobs. In that case, it was essential that the mob not be able to kill the characters in short order to give them time to figure out that they can't just murder their way through the challenge.
@Trish Ah, I think I can see what you're saying and that it's not there. I can't say I've personally felt the need for that (not with the homebrew side specifically anyway), so maybe that's why I didn't notice it's absence
If the guidance is "never make an unkillable monster" the user then has to know when to snap off that guide rail and strike out on their own. That's going to involve some try it and see if it works with your players.
I dunno - the 5e DMG's entire guidance about balancing monsters is fundamentally based on "how long does it take to kill the monster" versus "how much damage per round does the monster do"
the CR calculation is explicitly based on deriving a value from the monster's HP/AC and the monster's attack bonus/damage, I don't see how it's not obvious that changing those changes how challenging the monster is
@GcL I once designed an encounter where a golem had a LOT of HP and took half damage from magical attacks and magical weapons, but if they blew up these crystals on the side, each crystal lost dropped a chunk of HP and when both were gone it took double magical damage. It took them a couple rounds to figure it out but once they did the fight turned into "distract the golem and blow up the crystals" which was way more interesting than "punch this thing 100 times"
