This bug will need a ton of explaining because I don't think I have ever seen a bug like this at all in BCS.

  
in the first image you can see there is a bomb shooter inside another bomb shooter. one bomb shooter can shoot bloons the other can't shoot if directly clicked on. this is already unfair because i basicly lost a bomb shooter because of this.

in the second image you can see I played a bomb shooter in the bottom space, when i did that the banana farm in the space above was removed. this seems to imply that the banana farm was acualy in the bottom space and was only showing it was in the second bottom space. (this could also imply that the weird bomb shooter could have been shot if I targeted the mortar)

in the third image I tried placing a bomb shooter in the open spot above the one i just placed, once again the tower above was removed and I lost my mortar basically confirming everything i said in the second image.

in the fourth image i placed a tower in what looks to be an empty spot below the glitched bomb shooter. when doing so the glitched part of the bomb shooter was removed and i lost the game because i replaced all the towers i wanted to keep.

  
What this glitch appears to be is i placed the bomb shooter and the towers below didn't move below it to make space on the screen, but they did in the code. i think this happens because my bomb shooter managed to skip the part where the towers shift to make space, so all the towers were offset by 1 space besides the top bomb shooter.

Another bug. BUT this one is super important to fix because it lost me a game.