From the Super Mario Wiki
RamRams are enemies in Mario vs. Donkey Kong' that first appear in the second world of the game, Donkey Kong Jungle. RamRams hinder Mario's progress by ramming into him. Mario can pick them up and throw them onto spikes, which they are immune to. Mario can then use them as platforms to get over the spikes. RamRams can also be used as a weight to keep a switch activated. RamRams can only be defeated by dropping fruit on top of them. They slightly resemble the animal helper Rambi.
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