Being the Banshee being touched in someone's fantasy might be someone's fantasy, though. Can't hide from gay space elphs, really.
Okay I got one for Eldar and one for LSM Eldar Im obviously a warpspider exarch. My two wristblades slashing and piercing foes while my shoulder mounted wraith spinners firing on my enemies from afar. Bliping in and out before the enemy has a time to react. My Red, black, and white armor a mere blur to what my opponent sees. The green snake, my only calling card. LSM (Caentyr's shitty LSM OC "Agujam") I am a white scar. My roar is as loud as the thunder that is my steel horse I ride. They cannot see me, and it will always be that way as I cut through the foolish mob of orks, only to blast out on the other side like my power-sword through their skulls. My helmet off for them all to see if they could....my beard and ponytail flailing in the wind as the blood desperately tries to surf on the wind to no avail. My speed is next to none. For I am Agujam, rider of the 8th company and the 5th legion..... and I am the emperor's calvary!
@DongSlayer is right Being a Death Korps of Krieg grenadier and dying in a glorious charge is all I ask
My fantasy is to be the first Alpha Legionnaire in history who attempted to infiltrate the Eldar society by himself (yes, not Legion's human operative but a Legionnaire himself, implying I'd need to apply certain surgery to my body and face....meh.....) Basically I want to be a 7.5 feet-tall Eldar with bulging muscles and fists size of Eldar torsos....yeah
You could try passing yourself off as a successful recipient of a new eldar muscle-enlarger fruit. Begin by spouting lines such as "EXARCHS HATE HIM!" or "ASPECT WARRIOR FOUND REVOLUTIONARY NEW SLAANESH-PROOF MUSCLE BUILDER"
DID SOMEONE SAY SLAANESH?!?! As for power fantasy.. Being a Rogue Legion Commander and just pirating the shit out of the Empire. because then you get to hang out with all the cool folk like Free booter merc's, Rogue Traders , Chaos, occasionally the odd inquisitor will visit the home fleet. I'd have a special room for them .. Cypher might drop by talking his crap again.. We'd trow the wildest lewt party's invite some noise marines and rogue battle sisters. It ill be great!!
imagine waking up suddenly physically and psychically better imagine finding brothers with your very same dreams imagine going up the social ladder through hard work imagine finding the perfect soulmate and building a family imagine fighting for freedom with faith, will and courage imagine liberating a whole planet and making it better imagine leaving that world in the loving hands of your god as you sail forth between the stars in the search of a new home imagine being a Spoiler genestealer cultist
I'm surprised by the lack of inquisitorial based ideas, kinda, they do have a bad streak the size of the eye, but say you could overcome or at least mildly suppress the corrupting power of being awesome, not a bad gig and you have some the highest authority around. One other I didn't mention was something mechanicus, whether as an imperial knight or in a titan, I'd tend toward warhound or lord. What can I say, I like Mechs and enjoy mechanical stuff, but I'm too aggressive and impatient for standing around pushing buttons that fire missiles, I'd rather walk around and leave big foot prints and fire missiles.