It's not a game-changer or game-breaker, and it really is just for funsies. But boy, oh boy, is it amusing to go through your collection just to see what each pet would look like with an extra tinge of purple hue!
First let's take a look at the Dark Phoenix Hatchling without the spriest glow.
Now here it is with the glyph activated. Pretty neat, huh?
My alt priest will be going shadow more often than not in MoP just so I can play around with my pets. All I can say is that I hope all the priest collectors enjoy this new glyph to the fullest. Am I jelly? YES! ;)
Here are a few more screenshots of some of the more interesting companion plus shadow priest coloring combinations. Some of them almost seem to disappear with this new glyph!
In honor of the Midsummer Fire Festival starting today, I just had to try out the Searing Scorchling with the new glyph. I'm impressed with how awesome it looks!
I found the Disgusting Oozeling particularly amusing because it gave me a green glow while I gave it a purple one. It's a color swap! You can still make out some green inside the oozeling, though.
The Ghostly Skull was very interesting. It's already normally hard to see without any extra changes, but with the spriest coloring it gets SO much harder to detect. It could have also just been the location I summoned it at that made it hard to see; I haven't tried other spots yet.
Can you even spot it? I'll give you a hint: it's near the Zeppelin.
Here's another comparison screenshot. The Phoenix Hatchling before...
...and after! I'd put it in the same boat as the Ghostly Skull. If it didn't have that swirling mass around it, it would probably almost disappear with the added spriest tint.
And the best for last, the Spectral Tiger Cub looking a bit more evil than usual hehe.
These are just the tip of the iceberg. I haven't even gone through my entire collection using the new glyph, but I'm sure all of the companions look kick ass with their added purple glow.