Fire elemental

You chose to invoke a fire elemental. You break the stick and a living ball of flame appears in front of you.
“Attack my enemy” your order.
“With pleasure” answers the fire.
To your surprise he doesn’t move toward the goblin but he rushes straight on you.
You just have time to get out of the way of the fireball as it passes close to you. You turn to see his next attack and you discover a burning goblin behind you, a knife in his hand above his head. One more second and this knife would have been in your heart. You order the elemental to attack the second goblin too, but you have no answer as you realise that the fire elemental left once the goblin’s dead. The only flames left are dues to the combustion of the goblin.

The smell of carbonized flesh makes you sick but you have to stay focused; if one goblin is dead, one is still alive and he doesn’t seem playful anymore.