Consider using this spell to spike or to finish off wounded opponents.
Players should disable Obsidian Flame on their Heroes' skill bars and trigger manually; this spell is often used excessively by Heroes, causing them to accrue massive Exhaustion.
It would take at least 11 seconds to use this skill while it is Echoed, but, with an extremely high level of Earth Magic, you can kill the common PvP foe in that time unless they get healed.