Bloonarius Prime takes place in a swamp, with a large clump of trees and rocks blocking line of sight in the middle. There is a green river that allows for water towers to be placed. The color theme and swamp-like nature of this map strongly reflect Bloonarius, the first Boss Bloon in BTD6 and released on the same update as this map. The composite lane is significantly longer and has more intersections & bends compared to the prime rounds, making composite rounds significantly easier.
Strategy
Bloonarius Prime is among the most difficult Intermediate maps. The line-of-sight blockers in the middle, the lack of spots that have good coverage of both lanes, and the short length & awkward layout of the prime lane all contribute to this map's difficulty. The alternating lanes of this map make certain towers excel, and they are listed below.
The alternating lanes allow Corvus to reliably deal with the early-game with the spirit and occasional use of Spear. When placed at the entrance, he can constantly farm mana throughout the game. He saves up massive amounts of cash and allows expensive win conditions to be obtained, and Ancestral Might and Overload make his power remain immense in the late-game.
Geraldo excels on Bloonarius Prime for two main reasons. He works well with a wide variety of optimal towers on this map, such as Comanche Commander and Sniper Monkeys with Perma-Brew. He also excels on Intermediate maps in general, as his shop refresh occurs on Round 95 in CHIMPS if placed relatively early, allowing for much greater use of his most powerful items, such as Genie Bottle, for the hardest rounds.
Easter egg
Repeatedly selecting the left corner of the rightmost lake causes a crocodile to appear.