it's supposedly an egg. if you surround it with 3 penguin, it will becomes a baby penguin. btw, how did you trigger that background glitch?
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I know now how to hatch them but I'm stuck on level 22 which it took some time to solve.
And i use john gbac emulator since it has low storage (i mostly use it) because most of the emulator has large storage (they even got 200mb), and this emulator is below 100mb.
But thanks for the info.
BTW, are you the creator of country ball thing? Because I saw your name in the plastered.