Wyverns are what happens when a Medusa attempts to turn a Werewolf into a Gargoyle and fails.

I started off thinking about my own version of Brendan's differentiating weapon with properties other than how much damage they do  and then I started thinking about pikes and how cool it would be if PCs hired a bunch of pikemen to travel around with them but then I thought pikes are a lousy weapon in a dungeon, you're better off with a shortsword in those tight spaces then I was wondering about what kinds of foes or situations would it make sense for the PCs to hire a bunch of pikemen if not dungeon crawling and the answer to that is wide open spaces and enemies that are something like cavalry since historically that's what pikes were good against so that means beasts, animals, humanoids I suppose too but I like the idea of big scary beasts being fended off by a handful of guys getting paid like 5 gold a day and they're all scared shitless but their wizard boss is like "it'll be fine boys, just jab him if he gets any closer."

Dragons are a big beast but their fire breathing would render pikes useless, so it's gotta be a big beast with no ranged attack, how about wyverns?  Then I remembered how I want to link Lycanthropes with Medusas via Gargoyles like this: Medusa/Gorgon type creatures are really intelligent and really old and for whatever reason their turn to stone effect doesn't work against Lycanthropes the same way it does against every other kind of creature, instead of turning to stone they turn to stone but are able to move and think and they are forced to serve the Medusas who make them.  Maybe the ancient Medusa language Gorgole has a magic effect on them.  Then I think maybe some were creatures turn into something other than Gargoyles maybe their mutants, maybe they look away at the last minute maybe they drank an anti turn-to-stone potion made by a werewolf alchemist I don't know.  The whole Medusa/Gargoyle/Lycanthrope relationship will have to be explored another time, here's the sketch that resulted from the above silliness:

Sentient Spells

Sometimes through accident or strange purpose, a spell acquires sentience, personality and it's own goals or desires. A sentient spell can be scribed into a Magic-User's spell book. (it may already be there when it becomes sentient)  When the Magic-User attempts to cast the spell he or she must convince the spell to create it's effect. This will generally require the M-U to acquiesce to the Spell's requests. When a Sentient spell is encountered or created it's desires/goals should be determined. It will take at least one round to discuss the casting with the spell. The following modifiers should be applied to the reaction roll:

Roll 3d6 Take Highest 2 dice	If the M-U provides the spell with it's desires.*
+1/level lower	If the spell is lower than the highest level that the M-U can cast.
Roll 3d6 Take Lowest 2 dice	If the spell is greater than that which the M-U could normally cast.*

SENTIENT SPELL REACTION TABLE
2d6	Reaction:
2	Refuse and demand
3-5	Argue and request
6-8	Debate or concede 1/2 spell effect
9-11	Concede spell effect
12	Spell effect x2

1d6	Spell's Appearance:	Spell's Initial Method of Arguement/Debate:	Spell's Desire:
1	invisible	Charm	Freedom. If granted the spell may be erased from the caster's spellbook.
2	warm glow	Con
3	shadow	Sulk/Complain	Life Energy. If granted decrease caster's or victim's Hit Points.
4	crackle of electricity	Blame
5	vague, ghostly animal	Veiled Intimidation	Magic. If granted delete magic items (permanent) or spell slots (temporary).
6	inhuman, alien creature	Open Threats

*If a Magic-User attempts to cast a sentient spell that is of a greater level than he could normally cast and he provides the spell with it's desire, then roll 2d6 as normal.

I have not used this at the table yet.  It will probably change a bit when I do.  The above is what I would tell/show the Players. What I wouldn't say (at least not at first) is that stringing the spell along is kind of what this is all about.  Saying you'll give it what it wants, but putting it off.  Also the degree of freedom/amount of HP, magic items or spell slots is deliberately vague.  What ever the spell can convince the M-U to give it is what it gets!