Mushroom Grotto in Bloons TD 6 becomes more unpredictable in Alternate Bloons Rounds mode, as bloon types appear in a mixed and irregular order instead of following a standard progression. This is further complicated by the map’s darkness mechanic, which limits visibility and makes efficient tower placement more important than ever. To succeed, you need a flexible defense that can adapt to unexpected bloon combinations while maintaining strong overall coverage and control across all lanes.