Bloontonium Lab is one of the hardest tracks in BTD5, and is one of the couple Extreme tracks. Its three completely separate short paths that only come close together in the middle makes this extremely difficult to beat, especially on hard. If you don't get up a good defense quickly. M.O.A.B. class bloons will give you massive problems. Note that the strategies written below won't guarantee a absolutely win, especially on hard difficulty. These are merely guidelines to help you have a general understanding of what you need to do to beat the map.