The name Vulca comes from "Vulcan", the Roman god of fire and metalworking. He obtains his flame-like skills because of this.
Vulca's weapon name is Ignis, meaning fire in Latin.
When the game was in development, Vulca only had damage buffs whenever Vulca activated an ability. Since it was overpowered based on the community's comments, Vulca then had defensive debuffs whenever Vulca activated an ability. This can also be utilized as a buff, as you can use Berserk Blade quicker.
Vulca's Blazing Assault is the one of the only ultimate abilities that can ignore blocks.
Update 10.31.16 brought major changes to Vulca.
Strategies
Gun Stance is an effective way to build up Fiery Spirit.
Weaknesses
Vulca needs to build up damage in order to gain high damage, dodge his attacks and dish out your own damage to gain an upper hand.
Due to Vulca's naturally low defense, he cannot rush down opponents without being destroyed himself.
