Is Discord a good guardian?

[HorsesandMOARGaloar 300]

In my fanfic, my preferred ending (you can choose one of four timelines) is when Discord and Screwball (his daughter) escort Shelby to a spot where he is supposed to be taken home to Earth. Yet, in this Equestria, it's mired in a civil war, and some Aliens were the ones who mind-controlled most of all the sapient beings who live there.

Oh, and the Aliens had technology powerful enough to limit Discord's powers to whatever circumstances only they wish. Every time anyone dissents against the aliens, even the Princesses as well, they will be briefly electrocuted.

Considering Discord's manipulative, and wicked, personality (in the fanfics, he is reformed), how will Discord treat the Shetland pony along the way, amid the base trespassings, encounters with the psychotic Solar Empire/New Lunar Republic ponies (all waiting to catch him and exploit him for their axe-crazy ends), and the one barely-escape from Krastos the Glue-Maker?

Tl;dr: If Equestria were to be split into civil war between the Two Princesses and Queen Chrysalis, and all the ponies (minus Screwball and Lauren Faust, the latter imprisoned in a space fortress) are axe-crazy psychos, and the aliens order Discord to escort Shelby to the Canterlot Maze (where a portal to Earth is supposedly located there):

How will he treat Shelby, the Shetland Pony?

[Castle Bleck 19,353]

He'd be an Anti-Hero / Jerk With A Heart Of Gold.