Labor
Labor involved in the activity of playing Magic is as complex as the other components of the network.
Playing the game involves considerable labor, including recognizing and following the general game flow, interpreting card rules and ensuring correct gameplay (as understood by the players of a game), and providing one’s opponent with what is, optimally, an enjoyable social experience.
This labor is compounded by the labor involved in negotiating game rules and social conventions for one’s recognizable relevant communities: to what extent is any particular rules disagreement significant to the overall game? how acceptable is it (especially in a casual setting) to rely on an external arbiter or judge for rules decisions? how likely is it for this opponent to talk about nongame subjects while playing, or should any such conversation unrelated to the game be limited to pre- or post-game periods?
For those players interested in the fantasy lore that serves to connect cards together diegetically, there may be internalized labor of inventing a narrative that both reflects emerging game play and adheres (or not) to recognized principles of one or more Magic game worlds and character behaviors.