From the aspect of Arabic language the root Khalq (creation) occurs in three meanings:
1. To evaluate or estimate something.
2. To transform a thing into something else. For example to make tools from iron.
3. To bring something from non-existence into existence. That is to bestow existence upon something that did not exist before.
Without any doubt the third meaning is special to the Almighty Allah, but the first and the second are applicable even to human beings. In the ayats of the Holy Quran the root Khalq is used in the first or the second meaning. For example it is mentioned regarding Isa ibn Maryam (‘a):
“and when you would create from clay the form of a bird, with My leave, and you would breathe into it and it would become a bird, with My leave;”[5:110]
Here it denotes changing one thing into another.
So according to the first and the second meanings there can be many creators who , by the way, are all the creatures of Allah and are all dependent on Him. So it is correct to state that He is the best of Creators.
Ref: Ayt. Makarim Shirazi and Ayt. Ja’far Subhani., Religious questions answered: Logic for Islamic rules, Published by: Ansariyan Publications Qum, The Islamic Republic of Iran