Why It Exists
Border arrangements describe card shape: which edges are present. Every combination exists, from no borders to 1, 2, 3, or all 4 borders. This makes cards usable as simple tiles instead of only as flat ranked cards.
16 instances, 10 groups
Border Arrangements
Border arrangements describe which card edges carry border marks. Borders can be present or absent on every side, and if present can carry a point score from 1-4.
Uses in Play
Treat the edge patterns as paths, walls, gates, or adjacency requirements in tile-laying and map-building games.
Require corners, opposite sides, open or enclosed cards, or exact edge matches. Edge point values can add another mechanical or narrative meaning.
Relationships
Border score is the numerical counterpart to border arrangements.
Since scores follow a pattern across suits and rank, border distribution does as well.
Border zodiac is a related overlay that maps some border arrangements into zodiac signs.