To install it.
#pacman -S libreoffice
If there's language option choose that you needs, and the others just enter.
If done, libreoffice will available on office menu.
Here's the snapshot.
|Calc, or Excel on Ms.Office|
|Impress, Power Point on Ms. Office|
|Writer, Word on MS.Office|
Some feature that insteresting to me "Save as to PDF", so you can save document directly into PDF, you can create ebook with it. and without additional software. :D
And for opening microsoft file (docx, pptx, xlsx) the results is not 100% same, but looks better than open offices.