p.boxed
  | Three new pieces appear. All pieces are unique.

p.
  There are only one rook, one bishop and one knight per side in this variant.
  That explains the name. The king and queen are still there,
  and the three remaining slots are taken by new pieces:

ul
  li.
    The lancer 'L' is oriented and can only move in the direction it points,
    by any number of squares as long as an enemy isn't met
    (it can jump over friendly pieces). If an opponent' piece is found,
    it can be captured. After moving you can reorient the lancer.
  li.
    The sentry 'S' moves like a bishop but doesn't capture directly.
    It "pushes" enemy pieces instead, either on an empty square or on other
    enemy pieces which are thus (self-)captured.
  li.
    The jailer 'J' moves like a rook but also doesn't capture.
    It immobilizes enemy pieces which are vertically or horizontally adjacent.

p.
  On the following diagram the white sentry can push the black lancer to
  capture the black pawn on b4. The lancer is then immobilized
  by the white jailer at a4.

figure.diagram-container
  .diagram.diag12
    | fen:7k/8/8/8/Jp3m2/8/3S4/K7:
  .diagram.diag22
    | fen:7k/8/8/8/Jm3S2/8/8/K7:
  figcaption Left: before white move S"push"f4. Right: after this move.

p To reorient a stuck lancer,
ul
  li Just after being pushed: play a move which 'capture your king".
  li Later in the game: click on the lancer.

h3 Complete rules

p
  | The rules were invented by Jeff Kubach (2020), who described them much
  | more precisely on the 
  a(href="https://www.chessvariants.com/rules/8-piece-chess")
    | chessvariants page
  | . While the summary given above may suffice to start playing,
  | you should read the complete rules to fully understand this variant.