Custom Segments come with two custom operators; IN and CONTAINS.
You can target users with different values using the IN operator. This will deliver a message to any user that has a Custom Segment value IN the list that you provide.
This example below would send a message to any user whose AccountStatus Custom Segment was premium or vip.
You cannot use the IN operator with a Custom Segment that stores an array of values.
If your Custom Segment stores a list of values, for example a list of previous purchases or a list of categories, you can use the CONTAINS operator to message users whose Custom Segment CONTAINS a certain singular value.
This example below would send a message to a user if their PreviousPurchases Custom Segment contains the value "subscription_renewal".