Rules

Start: Randomly place 10 x white, 10 x black and 10 x red balls in a pyramid.

Play: Each turn, remove two balls of the same colour that are not visibly connected
           (i.e. not in the same group of physically touching same-coloured balls).

Removals may cause drops. One ball of the pair may (indirectly) support the other.

Aim: Remove all balls.

Notes

Games will take at most 15 moves. Not all games will be solvable, but most should be with careful play.

If the random starting position does not allow any moves, reshuffle a few balls and try again.

Try to remove balls that orthogonally connect two or more others of the same colour first.