Excellent question to reflect on my value as a team player! I guess I'm an integrator who creates common values and a common goal. I love to unite people into a team with the help of corporate culture traditions.
For early team members, I would always look for their strong belief in what we are building, because if the believe in it, they will be committed to our success more.
Afterwards, I would look for a combination of skills but the most important is responsibilty, being resourceful and ability to learn.
The ability to do think ahead and not rely solely on what you tell them to do. When they see a problem in the business and solve it on their own for you, that is the best.