Source: Soulbound by Vitalik

Non-transferability

A soulbound item, once picked up, cannot be transferred or sold to another player.

If you take the proverb that “those who most want to rule people are those least suited to do it” (Douglas Adams, The Restaurant at the End of the Universe) seriously, then you should be suspicious of transferability, precisely because transferability makes governance power flow away from the meek who are most likely to provide valuable input to governance and toward the power-hungry who are most likely to cause problems.

Game design

Soulbound in the context of video games (specifically Realm of the Mad God). I think this is such an interesting case study because the game itself is perma-death, meaning that items on characters are permanently deleted/lost on a character death.

Soulbound is an interesting mechanic that has had a lot of implications for gameplay and in-game economy:

  • Players cannot trade these items. This incentivizes participation for actual gameplay loops + events
    • For example, when the game decides to host an event by boosting item drop rates for certain dungeons, people actually just play the game more rather than accumulating wealth and just buying the items off of farmers seeking to make a profit
  • However, this enables a secondary (illicit) market that trades accounts rather than items. This only accounts for a very small minority of trades as the average user does not use more than a single account
  • There is certain prestige that comes with owning certain items (e.g. <1% drop rate from one of the most difficult dungeons in the game)
    • This is a visual signifier for one of three things: skill, veterancy, or dedication
  • As a result, organized groups for running hard and dangerous dungeons have emerged, with highly coordinated Discord servers with bots for managing headcount and role distribution (we need 2 healers! 5 people who can boost our damage!)
    • Some of the more elite groups actually have very strict requirements for entry (need to have 3 characters at the strongest stat cap, activity requirements, etc.)
    • All of these are volunteer run

By keeping the most prestigious items untradeable, it incentivizes more community involvement and recognition/prestige around the activities that yield those items. A lot of these items are extremely powerful and enable incredibly unique capabilities for characters. But as the game is permadeath, not a lot of individuals have the guts to use these regularly.