New variant? Highlander chess!

Hiya,

I'm sure lots of people come in here with what they think are their original variants only to discover they've been done before - I dreamt up what I called 'around the world' chess only to find out it existed as cylinder chess for over 1000 years - but hopefully this one is new.

In the Highlander films when you kill another Highlander you gain their abilities. So in Highlander Chess, when you take another piece, you gain their abilities. Whether or not that means that knights, bishops and rooks can therefore promote when they reach the 8th rank I'm not sure on - perhaps that would be the only ability that should be excluded. What do you guys think? My imagination is that this would lead to highly cagey, tactical, closed early games but then extremely sharp middle games. Or does this or something like it exist already?

Sounds like Absorption Chess.