Continuation of my 40k crossover comic strip from here >>907169 There’ll be quite a few pages before we see any true 40k stuff here though.  

 
“Sounds more like a memo than a letter Twilight”, stated Rarity from the far side of the carriage, waving a hoof nonchalantly.  
“So we’re being sent to retrieve this…item I presume?”
 
Dash folded her forelegs. “Since when did we play fetch? Doesn’t she have, like, guardsponies for doing things like this?”
 
“Must be something super duper awesome important to ask us though. What do you think it could be?”. Pinkie broke her short silence with her usual quick-fire speech.
 
The other ponies quickly realized she was going off at a complete tangent to the original conversation when  
“Cake..Or sprinkles..Or cake with sprinkles! Those things are gooood” came in to her ideas and went back to their own musings.
 
Pinkie had got one thing right though.
 
It had to be something special to warrant summoning the element bearers.
 
Off in a shadowy corner at the back of the carriage, a seventh pony watched the proceedings.
 
She held up her own scroll in a pale green glow, re-reading the message there, and sighed.
 
Looks like Twilight may find out about her hidden help.
 
Celestia had asked the unicorn to keep an eye out for her favourite student from the sidelines since Canterlot, and she had been sent to Ponyville when Twilight moved there.
 
Always watching from the background.
 
Despite her obvious intellect and near unparalleled talent, Twilight hadn’t realized she was being observed.
 
The observer closed her eyes. This could be a long trip and she wanted to be fresh when things got busy.