In the games probably Arceus. But he is not so great in the TCG.
EDIT: If you were checking their power in both the games and TCG, the answer above would be correct. However, in the anime or manga it's more complex. They are both "god" pokemon and who's power-level is the highest is strictly based in theory. In my theory for example,mew and arceus are brothers. In my theory it states that although mew would have a much higher iq, easily being able to out smart his brother, arceus' power level would be off the charts. Mew being the elder and arceus the younger. They lived in nothingness, until arceus decieded to create something anew. Thus the pokemon universe was born. As the elder of the two, mew felt that it was his duty to contribute to this . So he created the pokemon. Arceus and mew would create a yin and yang type situation, mew being pure and full of contentment, and arceus being harsh and unforgiving.
This question is world-wide and it's about to be answered! Here it is: Both Mew and Arceus are EXTREMELY powerful, but one is the ancestor of all Pokemon (mew), because he can learn every move. The other is the King of all Pokemon (arceus) because he was the first Pokemon (you may know, top floor of the canalave library, the book titled the original one) and the Pokemon most powerful. But arceus can't learn all moves, he can only become all types of Pokemon. So to wrap this question and put it to an end, MEW=ancestor, and copier. ARCEUS=king, and first of all Pokemon ARCEUS=the best Pokemon!
Arceus
Mew, mew was from a lower generation mew came first arceus did not create the world it created its home
The Irritating Wall: Blissey. Charizard, Arceus, Mewtwo, and Mudkip.
no arceus
you cant get a flute for mew but you can for arceus
mew is a little stronger a nd faster than arceus reminder mew can use all kind of power my gmail is nilawrence16@gmail.com peace is mew hidden power that can destroy any thing in cluding jugdment
Lugia Mewtwo Mew Deoxys On Diamond, Pearl and Platinum Arceus is the most powerful. You can only get it by using action replay.
Mew was made first before Arceus and mewtwo! that's why Mewtwo is called Mewtwo he would be called mew but mew was made already so they called it Mew number 2
Arceus was the Pokemon who created the world and the first Pokemon in it Mew therefore Arceus came first but still leaving Mew the first Pokemon.
if u mean r the sailor scouts more powerful then the mew mew then i yes yes becuz the scouts got more enemies , allies and powers
Mew and Arceus.