The first player controls Popo, a boy wearing a blue Eskimo parka, while the second player controls Nana, a girl wearing a pink Eskimo parka. The only tool they carry is a wooden mallet to Carve openings in the ice above and to club enemies. Each mountain consists of eight levels of colorful ice and a bonus stage. Standard, dull ice blocks pose no threat other than an easily disposed of barrier. Ice blocks that appear more square and detailed are indestructible forcing the player to take another path. Darker ice with diagonal lines act as a conveyor belt sliding the Eskimo either to the left or right. Finally, many mountains include Cloud-shaped, moving platforms as an additional hurdle. The bonus stage takes place at the peak. With a time limit of 40 seconds and no enemies, the Ice Climbers often face trickier jumps and multiple moving platforms. It is also the only place they can take back their stolen vegetables, most notably eggplants. Collecting just one piece of corn from the fifth bonus stage is the only way to gain an extra life. At the top of the peak, the condor flies overhead. Grabbing its talons before time runs out gives the player a large bonus.
Enemies encounter on their way up the mountains include the Topi, Nitpicker, and Polar Bear. Toppies come in two varieties: the seal featured in the Japanese version and the small yeti seen in western copies. While early U.S. releases featured the seal design, they were redone as a more imaginary creature over concerns of animal cruelty (seal clubbing). Toppies are the least threatening of the Ice Climbers' adversaries. Their aim is to keep the DUO from reaching further up the peak by filling in Gaps in the ice. To do this, a Topi scouts out a place the player has carved through the floor, runs back to its cave, and reemerges pushing an icicle to fill in two blocks. This process repeats till no more openings on their ice level exist.