Planeswalker Ruling

If I were to choose colorless or any color for that matter, would I be able to use Transguild Courier?

Transguild Courier 4
Artifact Creature - Golem
Transguild Courier is all colors. (Even if not on the battlefield.)
3/3

I ask because the oracle ruling states that the card is white, it is also blue, and black and red and green, as well as multicolor.

I want to know how this card would fit into our planeswalker games. I want to use cards like blessing of the nephilim. Hybrid cards are not allowed, so I would like a ruling on this card please and thank you.

My opinion would be that Transguild Courier would be legal for Planeswalker in a colorless deck since it is 4 colorless to cast.

Many cards in the game are one color casting cost, but take on attributes of other colors or a variety of colors. To me, the planeswalker event is based off of casting cost & whatever the card does after that is ok.

Blessing of the Nephilim - if I remember correctly, is an aura, right? Its one white to cast & gives a crit +1/+1 for each of its colors... That would be legal to use in a white deck for planeswalker.

The Transguild / Blessing combo would not be able to be used in planeswalker since they are different casting cost colors.

Thats the way I see the rules at least.

Agree w/ Laughing.

Thank you for the clarification