What do body and sparkle transmogs require?

The free transmog currency stops at the third step, the headgear slot. Glimmering Drift Shadows are what you earn without paying, and they carry Irisalis's transmog only through the early and middle tiers. Body and sparkling sit past that line, so there is no grind route to them.

Radiant Dream Shadows are bought with real money and used to change the appearance of legendary Aniimo, Irisalis included. The body and sparkling steps take a large number of them, which puts the best Irisalis skins firmly in paid territory. The cosmetic sets that include body and sparkling customization are only available as paid purchases.

Rolling carries a second cost. If you lock a transmog slot to keep a result you like, every roll after that costs the paid currency too. Locking a good result partway through means paying more for each roll that follows.