This skill completely prevents spell casting on the target: the spells will not fail, they will simply not activate at all.
Be aware that AoE spells that do not require a target, such as Inferno or Aftershock, can still be used to damage a character protected by this spell.
The only ways to remove Obsidian Flesh are non-spell skills that remove enchantments or spells that remove enchantments which do not need to target the character enchanted with Obsidian Flesh (e.g. Chilblains cast on a nearby foe).
