plymouth, mate, xorg and mirror

Alright, I got confused after the last post.
I found the boot process is stopped because system can't find plymouth.
So I tried install plymouth $ pacman -S plymouth but it saids error; target not found: plymouth. I searched another way to install plymouth on the web and found some people reports plymouth is buggy. It makes me think that I have to find the way to start Desktop without plymouth. But wait, when I checked installed packages $ pacman -Qe there was no mate, gnome or other desktop environment.
So what does lightdb try to start? I thought it tried to start desktop environment.
Anyway, I also found I didn't install xorg. It must be there if I want to start desktop environment. I installed mate via pacman and tried to install xorg but it failed. Again I couldn't reach mirror server (this time was Taiwan). I don't know this is because me or my machine setting is wrong or it occurs from time to time. But it is hard to think xorg can't be available because some settings are bit wrong because it's essential package for arch linux. Maybe I should work on mirror server setting.