Had kind of wierd experience a while back.
Ran a one shot adventure for low level guys (4th and 5th).
Moderate ability scores and the 5th level characters had very low wealth.
I didn't have huge amounts of time to prepare so i used an adventure from a really old (2nd ed) dungeon magazine. Most of the mooks in that adventure were gnolls.
Now these are experienced players and 4th level characters have zero fear of gnolls unless the numbers are huge. I didn't have the time to do a lot of customization so all i did was:
Change the description.
"Basically these guys are beefy really hairy humanoids. Just medium sized. But their face looks kinda bear like. Not that big though. Just at a guess you would think their bite does damage like a dagger. They have kinda stubby claws on their hands, but they don't look like they would make decent weapons."
They had exactly the same stats as standard gnolls and I ran them exactly like I have always run gnolls.
The characters weren't sure what they were. They made skill checks and I gave them the gnoll info. The players used more care, planning, and tactics than they would have against gnolls. Something new. Fun was had by all. I felt good like I had breathed life back into an old boring monster. Excellent!
Now comes the wierd part. Afterward, I told them what I had done. A few of the players were rather upset and acted like I had betrayed them or the game in some manner?!? It rather confused me.
Ha, my GM constantly does the same thing to my group. He does it out of a desire to use creatures that exist only in his own homebrew world (and so we don't get too comfortable with stereotypical monsters--i.e. "Ho hum, just another hell hound"), but uses existing creatures' stats because it's just faster and easier.
It bothered me the first couple of times I found out about it, but mostly because he has surprisingly little understanding of the CR system or game balance and would alter a couple of things about the creatures--give them extra abilities or whatever--and I was afraid he'd accidentally create something that would totally kill us. ("Wtf a dozen wights with earth glide vs. our level 3 party?!?")
However, I think it also sort of bothered me because it left me feeling sort of helpless or useless. I like being the know-it-all guy, but my near-encyclopedic knowledge of the Bestiary is totally useless in his world :) After a couple of games I (mostly) got over my frustration and started enjoying the novelty of the story and situations instead of worrying about identifying everything ooc, but I still hate when he changes things for no reason except to be "different".
If you went ahead and gave the players all the info they needed through Knowledge checks, then I don't see that you did anything wrong. Especially if they all had fun! I'd just make sure to have your new creature continue to show up in the story, or else you'll lose some in-game verisimilitude.
Perhaps I am just feeling uncharitable today, but it sounds like you have whiney, ungrateful players. You did something creative and they resent you because they can't guess the enemy stats? Were I you, it would be all custom descriptions henceforth. It is your duty to shatter their skewed perspective.
Monte Cook suggested this very thing in one of his design diaries. Bypassing player knowledge to present the PCs (and players) with a "new" challenge is a tool of a smart GM.
JD Webster's game got played so much we knew the monster by the die rolls. When I started running, I started altering my monsters almost immediately. My 'gnolls' became 'beastmen', much as you did yours, but I gave them more variety in appearance. Neither path is more right, the change-up being more interesting, especially if you follow wynterknight's suggestion and make them recurring foes. Yes, I saw the 'one-off' line.
Monte Cook suggested this very thing in one of his design diaries. Bypassing player knowledge to present the PCs (and players) with a "new" challenge is a tool of a smart GM.
See, great minds do think alike!
...Were I you, it would be all custom descriptions henceforth...
It would be tempting. However, I no longer live in the same state as those guys. We play maybe once a year now at best. It will prob be a couple years at least before my turn to GM comes up again.
Afterward, I told them what I had done.
This was the mistake. Whenever I've retextured a creature, I never tell my players what I've done. It kills the "magic". Anytime you take a shortcut to make your work easier, some players will feel like they're not getting your 'best'. It sounds psychotic, but that's the case. Personally, I'd drop those players quickly if they continue to think that it's all about them and fail to recognize your efforts.
Don't let it bother you, just avoid telling your players where the smoke and mirrors come into play.
Or the Hide in Plain Sight version...
Say "You come across half a dozen Orcs" and the party magically knows their full capability.
Say "You come across half a dozen Humans" and watch them get thrown for a loop checking to try work out and guess everything they can.
I have a couple of players who have all-but-eidetic memories. Altered descriptions of standard monsters is a must for playing with these guys. My advice? Never pull back the curtain on your magic. ;)
...This was the mistake. Whenever I've retextured a creature, I never tell my players what I've done...
I suppose it was. I just wanted to share my 'clever' idea.
I remember seeing a post from someone who re-textured an Erinyes as something very different, although I forget what (maybe a whirling cloud of something?). What really stuck with me was the description of it's spell resistance. Effectively, when it resisted a spell, rather than just "The spell fizzles", it was more along the lines of "The creature reaches out with one of its appendages and swats the spell away from it. No effect."
So you can retexture abilities, effects, and spells ("The necromancer flicks his palm, and five small skulls fly off it. They fly around briefly, before all zeroing in to smash into you with tiny explosions. Take 5d4+5 damage.") to create that sense of "We've never seen this before". It doesn't just need to be an entire creature reskin.
I would say it's fine, with a few caveates, and these comes from my particular play style;
The PC's(not the players) should have some knowledge and expectations about their world and understanding of the creatures in it. If you live next to a giant nation of orcs who raid down from the mountains on a regular basis, it should be easy to know an 'Orcs' capabilities in general. On the flip side, if your characters have never encountered one before, and have just come to the only island in the world were orcs live, than the PC's shouldn't know anything about the strange Green Humanoids they are encountering, and thus the players shouldn't either.
It can be fun to try and align player knowledge with PC knowledge. It will never always work out, but it can be fun. Frankly I kind of any people who don't know every creature in the various Beastiaries(thankfully my knowledge has eroded over time) and can great each new encounter with a 'WTF is THAT!'
..The PC's(not the players) should have some knowledge and expectations about their world and understanding of the creatures in it. If you live next to a giant nation of orcs who raid down from the mountains on a regular basis, it should be easy to know an 'Orcs' capabilities in general. On the flip side, if your characters have never encountered one before, and have just come to the only island in the world were orcs live, than the PC's shouldn't know anything about the strange Green Humanoids they are encountering, and thus the players shouldn't either...
That is what I felt I was doing with the Knowledge: Dungeoneering checks. A few pretty easy checks and they had all the information short of reading the entry in the books.
They are typically a little stronger and tougher than the average human. They're not usually as tough as say bugbears though. Etc...They had even pretty much narowed down their stats (except for some reason they kept think I said they had a high wisdom even after I corrected them about it).