Crokinole

No — shots must be made by flicking the disc; pushing is not legal (page 1).

Yes — when one or more opponent discs are on the board you must try to hit an opponent's disc (directly, via ricochet, or by knocking one of your discs into theirs); if you fail to hit an opponent's disc your shot disc is placed in the ditch and any of your (or your partner's) discs hit are also ditched (page 2).

After a shot, all discs touching the Starting Line are placed in the ditch (page 2).

A disc completely in the 20 Hole is removed and set aside for scoring, but a disc leaning into or balanced above the 20 Hole stays where it is and is not removed unless it is knocked into the hole (pages 1–2).

No — if there are no opponent discs on the board and your shot ends in the 10 Zone or 5 Zone, that disc is removed from the board (this rule is used at the World Crokinole Championship) (page 2).

If a disc is touching a scoring line it counts as the lesser value; at round end count discs in the 15/10/5 zones plus any 20s set aside, then subtract the smaller total from the larger to determine points awarded for the round (page 2).