a shot in the dark
an attempt at something without much hope or chance of succeeding
The attempt to find the small boy was a shot in the dark.
Rules to play Ildado
When playing online, your bingo cards are randomly selected for you. Most online games give you 3 or 4 cards. Other games let you take more.
Every online bingo game has a caller or a display board for the bingo numbers. The game pattern is also displayed. Some games automatically mark the numbers on your card for you.