Knowing very little of Buldur's Gate (only played one game) if this is a rakshasa then shouldn't this be a demon like the others in Magic?
It could be because Demons and Devils have reversed roles between MTG and Forgotten Realms.
In D&D in general, not just FR, Rakshasa are fiends (devils).
D&D Devils encompass a much wider range of creatures than the MTG stereotypical 'naughty imp' depictions. Pit Fiends for example are devils, not demons.
I wasn't sure how much of D&D was considered Forgotten Realms that was my bad assuming that FR was just considered the general universe oops. But friends who know more about the general stuff had mentioned the demon/devil thing before.
I'm not sure when they got backwards hands. It isn't that way in my first edition monster manual, and not in 3rd edition illustration either (which are the editions I've mainly played). By fourth edition, the artists have clearly been given the memo. I googled around a bit, but mostly I got people saying "why do they have backwards hands though" and a few references to a TV show that inspired Gary Gygax to put them in the game.
But regardless of all that, this dude is pretty nuts. Another (and cheaper) Pitiless Plunderer is a scary thing, even if it doesn't have as combo-centric a trigger.
I like treasures, but I think they're hammering the concept a bit too hard in recent years.