Hello Liingling,
Unfortunately, I will be
Rejecting your map.
Like others have mentioned, the theme is unoriginal as there is already a UFO map. Please refer to the document in this thread -
https://manacube.com/threads/parkour-list-with-theme.20194/ to make sure that your map idea is original.
The build isn't great, it is accurate to a UFO, however I do feel that it is quite plain. I would suggest trying to add a bit more shaping and detail, so your build can overall look more attractive.
The parkour has variety which is good, there were a few parts that I feel were a bit repetitive, but overall you did use a nice variety of blocks and items to create original and enjoyable jumps.
The length and difficulty are good for an easy map.
Thanks for submitting your map! I hope to see more maps from you in the future.