What other illusions should guise be.
 

Would be cool if there where like illusions per era.

So eventually u get like that mushroom man illusion. Maybe late kunark. Gives some crazy good factions too.

bring back the burnoose of the halfbreed and jaggedpine forest

Bristlebane.

Also, whats the lore to Guise. Why is a dead frog assassin needing a dark elf form. What is the story there? Is it for a future infiltration? Something regularly used by the froglok ghouls? Where does this form get them into so they can perform their assassinations?

Serrated could be by design to make the pull out more dangerous.

Alternatively it could suggest the blade was originally smooth, but some of the assassin’s blows were parried by an even harder blade (I mean the dirk is bone), leaving the dirk full of notches.

Thinking more deeply, dirks are weapons I’d associate with barbarians. I wonder how the frog got hold of it? Was it crafted by a barbarian from a mammoth bone? A goblin bone? Ice skeleton bone? So many questions!

The short answer is a Troll Shaman of Innoruuk caused all the dead frogs in the first place.

I can't find any lore to support it, but isn't one of Innoruuk's nicknames 'the Deceiver?

Basic Satan analogue in that aspect.

I just want the stupid zoro hats halfling guards wear. Guise should just put that hat on your head and leave everything else the same

Bunch of great suggestions.

Undead frogs was innoruuk. Dark elfs = innoruuk. I always assumed it was some plane of hate thing that got into the assassins hands for working directly for innoruuk. Probably to kill some ranking dark elf noble that was becoming a threat to innoruuks plans or influence. And the frog just kept it.