The Welcome card, Actions family, yin polarity, evokes a door opening to the unexpected. It signals a willingness to let in what wasn't planned. This card invites you not to close too quickly a door that has just opened.
In Oradia's mirror-card system, Welcome answers to Create: the two don't oppose each other, they answer each other, like two sides of the same movement.
This page gives the card's general meaning. In a real draw, the Welcome card is always read in relation to the other cards drawn and the intention set at the start — it's that combined reading, unique to each draw, that the online oracle develops.