Enemies encountered on the way up the mountains include the Topi, Nitpicker, and White Bear. Topis come in two varieties: the blue seal featured in the Japanese Famicom "Ice Climber" release, and the short yeti seen in Western versions and "Vs. Ice Climber". Topis have the ability to fill in holes in the floor with ice. To do this, a Topi scouts out opening in the floor, runs back to its cave, and reemerges pushing an icicle to fill in two blocks. This process repeats until no more openings on their layer of ice exist. The Nitpicker is a small, mountain-dwelling bird that swoops down from icy caves on the levels' edges. Unlike the Topi, which is confined to one floor of the mountain, Nitpickers can cross over multiple ice layers. Taking them into account along with moving platforms and sliding ice, timing jumps can be more difficult. The final enemy is the bipedal White Bear. This enemy, wearing sunglasses and pink speedo, appears on screen only when Popo and Nana take too long to advance. Pounding the ice, the Polar Bear forces the screen to move up. If an Eskimo is forced off the screen, the player loses a life. Other obstacles include deadly falling icicles. These can form on the bottom of any type of platform. After a few successful mountains climbed, all enemies' speeds increase.