I encountered this while reading Astérix. The line of dialogue, uttered by Cleopatra to an architect building her a palace, is as follows:
Je te préviens, Numérobis, Amonbofis, ton concurrent, t'en veut beaucoup d'avoir été choisi à sa place pour construire le palais de César.
I understand this to mean "I should warn you that your competitor Numérobis wants very much to have been chosen instead of you to construct Caesar's palace."
However, the t'en is odd to me. Why not omit that and say à ta place instead? Is this really the best way to phrase that? I would never have known to write it that way.