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Sci-fi/time traveller cartoon from the early to mid 2000's.
The plot goes like this:
A time traveler was in some sort of training mission. Whilst he was on this mission he witnesses this girl that was going to get killed (I think this was taking part during the French Revolution). He saves the girl but it somehow causes the Earth to just disappear as if it had never existed. After this they go on an journey to find out what happened.
I remember seeing it when I was growing up in Portugal and I think it either aired on Panda or Panda Big.