Another Friend for the Hopper?
Introduction
Do you think that 3 Grasshoppers and a King can checkmate? Hi. This is a third part of the King and Grasshopper checkmate possibilities. Let’s dive in!
Well, can 3 checkmate? They must be able to!
Ummmm...no. They can’t checkmate. Remember that for a Grasshopper to check, it must be behind another Grasshopper. There is only one pair, so the last Grasshopper doesn’t add any impact against the King. It is possible to stalemate the opposing king, though, because the King doesn’t need to touch the opposing King to take away his flight squares.
Update
I have now changed my view about this. It is possible to checkmate a king with a king and three grasshoppers (it took 60 moves for me, and I hope it doesn't for you). It isn't possible to force checkmate, though.

57... Kg8 was played. There is a forced mate in two here. Can you find it?

Gf8+ is the right move. Then Kh8 is forced.

What is the checkmate in 1?
It's Gg8#.

Goodbye
We are nearing the end of the series. Hope you enjoy the last installment!
