Knights of Tethyr
Crystalline Devil - took form of a large emerald - deceased
Emerald Form = 2" diameter glowing emerald that looks to be worth about 500 GP
Devil Form = A gem coated humanoid with a cruel twisted face, jagged teeth, and terrible talons like shard of broken glass. Its feet, however, are soft and bare allowing him to sneak about.
Sir Bruce first came upon Esmeraldoch in gem form on the person of the Blort, the goblin chief. He took the gem into his possession not knowing its devilish secret. But at varying times was hit by the command and suggestion spells of the devilish gem. Finally at the druid grove of Felicity Briarpatch, Esmeraldoch took devil form and attacked. He said:
Blort was easy to command but your will is strong. You must be broken. The Master cannot abide one such as you prying into his affairs. I Esmeraldoch will slay you.
During the battle, Sir Bruce slew the devil.