UFO blocks are interactive objects in Graveyard Maniacs.
UFO Blocks are yellow and show a grey ship withe a blue glass window, a green orb underneath it, and two yellow dots on its grey part. The UFO that is summoned by the blocks has a large blue glass window attached to a circular grey disc. That disc constantly spins and four yellow dots are located one it.
UFO Blocks always appear fours. Once all are pushed together they will disappear and a giant UFO will come and abduct all enemies in the level. It is uncertain what happens to those enemies though they are probably destroyed since candy is dropped around the level as if the enemies were killed normally.