Hey!
Im looking for Flammidus card:
The question is, is it summoneable? and if it is where do I find the boss?
Some people have been posting links of it in-game shout, check if it is devil-type, if yes, sorcerer can summon it.
As for location, my best guess is Topes Fortress, since the mobs there have similar face modeling.
115 Dgn final boss! You’re welcome.
It is a demon so it can be summoned 
Thanks for the info @AquaSama, ill do that dungeon more often then (never did it cause i never needed to do it >.< )