Bucket is a tool that is used to carry water, milk, or lava. Making a Bucket of Water is done by having the bucket in hand and right clicking a water source. Making a Bucket of Lava is done by repeating the same process but with a lava source. A Bucket of Milk is however done by right clicking the empty bucket with a Cow or Mooshroom. Further information on Buckets can be found in How to make a Bucket in Minecraft.
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