I was preparing an adventure and wanted approximately a CR7 giant crab. You would think that with three Monster Manuals, I would have just what I needed. Think again.
Fortunately for me, I have taken to heart advice given by others over the years and I can look past the flavor text in the MMs. Do not get me wrong, I like the flavor text, and it is valuable. However with three Monster Manuals I probably have all the monster stats I will every need. (sorry publishers. though I am open to your marketing wiles - go ahead and sell me a bestiary for which I cannot live without possessing).
Quick scan through the books.... looking for a CR7 creature with two attacks (claws) and decent AC (hard shell)... ah there it is: Umber Hulk.
A few changes to be made: remove the confusing gaze, increase the natural AC, reduce the burrow speed, add some damage resistance against cutting/stabbing weapons (DR bludgeoning) and presto we have a giant green crab. The DM adds his own flavor text and we are off and running with about 5 minutes work.
I especially like creating new monsters with new descriptions that are exactly the same as monster stats in one of the Monster Manuals just to mess with the players who think that memorizing the Monster Manual is a fair and helpful thing that players should do. It irritates me that characters who have never seen a monster before are able to share helpful advice on how to slay this mystical beast before them. I guess that is my version of the Gary's Nilbog to confound players. Heh.
What do you say? DM's do you struggle with finding new monsters? Do you recycle stats? Are you satisfied with a small number of Monster Manuals? Players how do you feel about the DM's constant quest to come up with new monters? Do you like it or are your frustrated that your long hours reading bestiaries go unrewarded? Do your recognized when you have been Nilbogged?