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Round 10,000 is the round limit in Bloons TD 6. The first predetermined round beyond Round 263, it consists 200 very dense Fortified BADs each with 3,954,517,520 health that could pass through the whole track in one second, even with fast-forward off. Technically, it is still a random round, as the bloons consist of two sets of 100 fBADs, and one of them are stacked with zero spacing.
Rounds 10,006 and above also consists of waves of the same bloon, similar to Round 10,000. The only difference is that each Fortified BAD gets 200,000 extra health and 412,000 extra RBE every round. As every round past 10,006 always spawn 200 Fortified BADs, the round RBE follows this formula:
790,903,504,000 (Round = 10,000)
Round*82,400,000-33,096,496,000 (Round >= 10,006)
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