Glossa Anura, Another Transformative Spell

Description:  A quite modest spell that even an average apprentice can reliably manage, albeit one of limited utility.  It requires only a short incantation to evoke, although the subject of the magic must be visible and within arm's reach unless the caster is the recipient.  While it can be cast on any living creature there's little point in doing so on animals and other creatures incapable of speech.  Depending on circumstances it could be regarded as either boon or bane by the target. 

Effects: The spell's target becomes capable of speaking to and understanding any batrachian creature, intelligent or not.  This includes frogs and toads of all kinds, froglike supernatural creatures such as toad demons and chaos croakers, and various anthropomorphic frog-man species.  Normal speech and even spellcasting is still possible although the subject's voice takes on a phlegmy quality that some may find unpleasant.

The spell also physically transforms the subject's tongue, which becomes as proportionately long, elastic, and sticky as a frog's.  It can be used in a similar fashion, although without a lifetime of practice their skill at employing the modified organ will be erratic.  Employing the "glossa anura" to execute a stunt of some kind can be attempted once per round in combat situations, or whenever desired in other circumstances.  Doing so requires enough concentration to preclude spellcasting, and interrupts singing and oratorical feats.  Each stunt has a simple 50% to succeed, although the GM may apply circumstantial modifiers as desired.  

Examples of possible stunts include:

• Suddenly snatching a visible object small enough to hold in one hand from anywhere within ten feet.  If the target is being held, this requires an roll-off comparing each person's strength, with the attacker allowed to roll twice and take the better result and winning ties.  Attempting to snatch a sharp or pointed weapon this way is risky, with the attacker taking basic damage from the weapon if they fail to gain control.
• Striking a target with a harmless but stinging tongue-lashing.  This disrupts concentration and spellcasting, as well as being startling, unpleasant and generally insulting. 
• Depositing a glob of sticky goo on a target too large to snatch away.  Hitting a target in the face or eyes is even more difficult than other stunts, with only a 25% chance of success, but the victim will have a 50% chance of being unable to take any effective action for the next round (or about ten seconds outside of a battle) as they wipe the goo from their eyes, mouth and nose.  Less ambitious uses of this stunt have the normal chance to succeed, and can stick objects (such as the pages of a book) together, soil clothing, instantly render comestibles unappetizing, or perform similar acts of petty vandalism.

The spell is surprisingly long-lasting, enduring from casting until the next dawn.  It cannot be ended early without employing countermagic, which surprisingly has a 25% chance of failing with each attempt.  Involuntary targets of the spell may attempt to resist the effects as normal for your game system.

Possible Origins: Presumably some mage wanted to be able to speak to toads and frogs for some unknown reason, and this was the result.  Given the other uses the spell can be put to, another possibility is that some child prodigy created this incantation as an apprentice for less scholarly purposes, ie pranking his teachers and classmates.   

Complications:  The spell produces a slight alteration in the subject's voice as noted above, and may cause involuntary drooling when distracted or unconscious.  Quite a lot of drooling, actually.  It's pretty gross.  Dimensional distortions required to accommodate the enlarged tongue also makes getting dental work done during the spell's duration ill-advised at best.

In the unlikely event that some magical effect attempts to transform the target of this spell into an actual frog or toad, attempts to resist automatically fail but the victim will revert to their normal form at the next dawn.

Design Commentary:  This post was inspired by the Tongue of Frogs spell over on the Ancient Vaults & Eldritch Secrets blog, which I've riffed on in the past to good effect.  Always nice to find some outside inspiration, and Bat's blog is a good source of it.