SPOILERS ON THIS PAGE. DON'T READ IF YOU WANT TO FIND OUT YOURSELF WHAT THIS IS.[]
Tim is the final boss. He says that he needs 200 balloons (not bloons), but if you leak 200 you lose. Just play like you would anything else. You fight him as soon as you beat moon temple 3. He is a face wearing a gold crown that has a Bloon spray like the Flower Bounty boss, and attacks, all sprayed out like the Flower Bloon does. However, instead of only flowers, he can also use darts and mighty Moab stunning attacks. Also, he spawns super shield ceramics.
After Tim is killed, Dark Tim will emerge. He is like Tim but stronger and harder. He has stronger and larger attacks, and can summon super shield ceramics.
Both Tim variants give you money when attacked, similar to the lit Moab from the goodie store.
The player battles Tim on an upside down version of Monkey Meadows, with a reversed arrangement of BTD5's main theme. Eventually, the music will transition to the music from Bloon Oasis, once again in a reversed arrangement.