Thanks Bernd. I just received the card and mis-understood the advantage. I thought you actually had a 4th die. The back of the card is clear with the conditions that it isn't a physical die:
'The player Owns and imaginary white die valued at 1. The die counts as an additional white home die with a value of 1 when fulfilling the conditions of cards (and is included in the sum of the home dice). The player startsthe game with 1 Talent more (due to the sum of the Home Dice'.