Impasse is probably the most difficult rule of shogi and the fact that there are many versions of it doesn't really help. In July 2021, lishogi switched from the Try rule to 27 Point System, so let's take a look how it works.

This is very similar, if not the same, as the impasse rule, you might know from other shogi sites. This is an official rule that is also documented here.

The only difference is that on lishogi you don't need to manually declare the impasse. If you meet all the requirements at the beginning of your turn (before making a move) you will automatically win the game.

The requirements are:

• Your king is not in check
• Your king has entered opponent's territory
• You have 10 other pieces in the opponent's territory
• You have 28 points in total if you are sente (black), or 27 points if you are gote (white)

Now let's take a deeper look at each one of these.

Check

You can't win if you are in check. Nothing too complex about this. Just keep in mind that your opponent might prevent you from winning by an impasse by checking you.

Entering king

This is also relatively straightforward, your king needs to be in your promotion zone - the three farthest ranks away from you.

10 occupying pieces

Other than the king you need to have at least another 10 pieces in the opponents territory.

27/28 total points

• Rooks and bishops, promoted or not, count for 5 points each.
• Every other piece except the king is worth 1 point.
• King doesn't count

The pieces that count towards this total are the pieces that are in your promotion zone and also all the pieces you have in hand. This means that pieces on your 1st to 6th rank are ignored in the count.

Impasse calculator

All of this is a lot of counting, therefore to make it easier for you to know how close you are to winning (or perhaps losing) by an impasse, we got an impasse calculator. It shows you whether your king has entered, how many pieces you have in the opponent's territory and the total value of those invading pieces and pieces in hand.