Mega Coin Squad

Not missable. There is a single Mega Coin to collect from the end of the 4th level of each world. This 4th level has no secondary requirements, and only requires that you defeat all of the enemies that spawn in order to complete the level. The enemy spawn points and which enemies spawn are always the same, so you can quickly memorize each level across your multiple playthroughs. Once all enemies have been defeated, a Mega Coin will spawn, which you must then pick up and take to the piggy bank. Depositing the Mega Coin will end the level and unlock the associated achievement for completing each world.