Like MOABs, BFBs can pressure the opponent with a high-HP bloon while gaining Bloontonium. However, BFBs are less flexible than MOABs, due to its 1 extra Gold cost, but have +100 HP for the same delay. So, the BFB is best combined with MOABs to maximise mid-to-late-game pressure.
Ignoring additional income, Player 2 can send a BFB on at least Round 3 (Round 2 on High Finance), compared to Round 4 (Round 3 on High Finance) for Player 1.
One MOAB and BFB give exactly enough Bloontonium for Obyn’s Spirit Strike.
For Adora, two BFBs are enough for 3 active Sun Shields, and one BFB + Rainbow Bloon or Zebra Bloon give exactly enough for Ultimate Sacrifice.