If you have placed a Tier 4 tower for more than 20 rounds and you also have a Tier 3 Specialty Building for it, you gain the abillity to get it's elite upgrade at a cost of money. Elite upgrades can enhance the towers attacks and abillities and can even add new attacks and abillities. If you use an Elite Training Dummy, you can upgrade an elite upgrade without having to wait the 20 Rounds. Here is a list of each tower's Elite upgrades:
- Juggernaut becomes: Explosive Spikes ($3500). Explosive spikes explode every 3 bloons they hit anything BUT they still pierce through lots of bloons. Might cause lag though.
- Super Monkey Fan Club becomes: Servant of the Monkey God ($12000). This makes Super Monkey Fan Club turn the dart monkey who activated it into a Sun God instead of a Super Monkey but the other Dart Monkeys turn into 1/0 Super Monkeys instead. Also allows the dart monkey's darts to pierce as many bloons as a Sun God would.
- Ring of Fire becomes: Fire Aura ($4000). Fire Aura is a constant ring of fire that pops 2 layers every second.
- Blade Maelstrom becomes: Razor Shredders ($3000). Blades now have 8 popping power each. Blades now move A LOT slower, but any bloons it their path get shredded once every 0.5 seconds. Blade maelstrom blades are still the same.
- Cripple Moab becomes: BOOM! Bloonpop! ($70000). This makes the Sniper Monkey have a 20% chance to do a critical hit which completely destroys the bloon which it is firing at. Bosses instead take 1000 damage. Makes the Sniper Monkey's regular shots deal 30 damage a shot. Also adds an abillity: BOOM! Bloonpop!. BOOM! Bloonpop! will make the Sniper Monkey's next shot have infinite pierce and has 100% chance to crit. CD: 120 secs.
- Supply Drop becomes: Dual Snipers ($30000). This makes the Sniper Monkey hold 2 Semi-Automatic Rifles which can aim seperately (You can choose different targeting options for both of them) and also adds an abillity: Popping Spree. Popping Spree makes the Sniper Monkey shoot as fast as a 3/x Dartling Gunner for 10 secs. CD: 90 secs.
- Glaive Lord becomes: Glaive Master ($12000). This makes the glaive that circles around the Glaive Master circle a lot faster. Adds an extra glaive to the circle and also controls three permanent glaives that will hover on one bloon at a time, slowly but surely shredding it to bits. Also still has the glaive ricochet.
- Turbo Charge becomes: Chemical Weapon ($5000). Bloons hit by the Bionic Boomer have a 20% chance to get a completely random status effect. This status effect can't be helpful to the bloons. MOABs have a 10% chance to get inflicted by a status effect that can effect MOABs.
- Bloonjitsu becomes: Monjitsu ($4000). Monjitsu allows the Ninja Monkey to shoot 2 kunais along with 5 shurikens. Kunais pop 2 layers and has a popping power of 8. If they pop 8 bloons, they explode. Will also explode if it hits something that it can't pop, like lead bloons.
- Sabotage Supply Lines becomes: Sabotage Rubber Supply ($5500). This makes Sabotage Supply Lines stop bloons coming out for the duration and makes the bloons that were supposed to come out, come out at half speed.
- Bloon Impact becomes: MOAB Impact ($4000): Bloon Impact now stuns MOABs for short amounts of time.
- Moab Assassin becomes: Moab Annihalator ($10000). Moab Annihalator allows the Moab Assassin ability to hit up to 5 moab class bloons now.
- Viral Frost becomes: Mystic Chill ($11000). Mystic Chill allows Arctic Wind to slow MOABs a little bit and also pops bloons once every 2 seconds they are in the arctic wind.
- Sub Zero becomes: Fragile Ice ($12000). Frozen bloons can now be popped by any tower and when they are they lose 3 extra layers. Also freezes MOABs for an extremely short time, and MOABs can also shoot ice shards.
- Bloon Liquefier becomes: Extreme Corrosive Solvent ($20000). Extreme Corrosive Solvent can dissolve MOAB class bloons 15 times per second! Doesn't slow them though. Also dissolves regular bloons 15 times per second.
- Glue Striker becomes: Incredibly Sticky Mixture ($9000). Incredibly Sticky Mixture allows the glue gunner to slow down MOABs a little bit. It also allows Glue Splatter to splat up to 18 bloons instead of 6.
- Aircraft Carrier becomes: Ferry ($12000). Ferrys can carry towers. It can also use any attack that exists in the game. It could shoot a x/0 dart monkey dart or it could also shoot a 4/x Super Monkey sunray! It's completely random and can be very strong or very weak. It also still shoots outs monkey aces.
- Monkey Pirates becomes: Davy Jones Locker ($10000). Adds a new abillity that flushes all non-MOAB bloons into Davy Jones' Locker. (Basically, death.)
- Spectre becomes: Assault Squad ($8000). Assault Squad gives the Monkey Ace 2 orbiting 2/3 mini Monkey Aces. The Spectre's darts now become huge and pierce through a lot more bloons.
- Ground Zero becomes: Miniature Nuclear Barrage ($14000). Miniature Nuclear Barrage allows the Monkey Ace to shoot nukes instead of darts occasionally. The nukes have a huge explosion radius and can pop 3 layers.
- Temple of the Monkey God becomes: Supreme Monkey God ($90000). Supreme Monkey God gives camo detection to itself and other towers in it's range. Shoots giant, piercing suns that pops 2 layers per frame. Abillities gotten from sacrifices are further enhanced, e.g. MOAB Mauler would give the Monkey God missiles that dealt 10x damage to MOABs and Spike Factories would let the Monkey God drop spikes as well.
- Technological Terror becomes: Deathbot 9000 ($45000). Deathbot 9000 has 2 extra arms and rapid firing heat seeking missiles on its back. The Technological Terror abillity has a slightly bigger range and COMPLETELY destroys everything, even ZOMGs. The plasma beams that it shoots out can be either red, blue, green, yellow, purple or orange.
- Tempest tornado becomes: Electrical Storm ($10000). The Monkey Apprentice will also launch out a storm cloud which shoots tornadoes and lightning at high speed.
- Summon Phoenix becomes: Meteor ($15000). The Monkey Apprentice's Dragon's Breath has double the popping power it had before. Abillity: Meteor. Meteor allows you to launch a metor at a huge area. The Meteor deals 2000 damage in it's radius and burns all bloons in it 10 layers a second. The burning meteor lasts for 5 seconds. CD: 120 secs.
- High-Energy Beacon becomes: Medical Village ($13000). Medical Village increases the health of towers in it's radius by 1.5x of it's maximum health and also heals them for 5 health per round.
- MIB Call to Arms becomes: Weapons Research Labratory ($20000). Weapons Research Labratory allows towers to pop 1 extra layer per shot.
- Banana Research Facillity becomes: Experimental Banana Cloning ($17000). This, in addition to spewing 5 cartons of bananas, makes the Banana Farm spew a box of bananas out every 5-10 seconds.
- Banana Investments Advisory becomes: Banana Lottery Agency ($17000). This generates $2000 every 20-100 seconds. This $2000 will be deposited and can collect interest. Can now also store up to $50,000.
- The Big One becomes: Bloon Bursting Bombs ($15000). Bloons Bursting Bombs allows the Mortar Tower to shoot HUMONGOUS bombs that pop 7 layers each. Burny Stuff now also burns through 3 layers and can affect MOAB-class bloons.
- Artillery Battery becomes: Dual Aiming Cannons ($8000). Allows the Mortar Tower to aim at 2 spots at once but shoots at them one by one. The Pop and Awe abillity now also affects MOABs. Shoots a bit faster.
- Ray of Doom becomes: Ray of Extreme and Complete, Utter Obliteration ($40000). This upgrade gives the Ray of Doom infinite popping power and allows it to pop 2 layers per frame. Abillity: Apopalypse. Apopalypse makes the Ray of Doom do 30 layers of damage per frame and doubles it's width for 10 seconds. CD: 120 secs.
- Bloons Area Denial System becomes: Automatic Heat-Seeking Missiles ($20000). This upgrade alows the Dartling Gun to shoot faster and the missiles to seek the nearest bloons around. Also makes BADS deal 2x damage to MOABs.
- Spiked Mines becomes: Burning Trail ($14000). Any Spiked Mine that explodes leaves fire in it's trail for 10 seconds that pops bloons 5 layers per second.
- Spike Storm becomes: Hypersonic Energised Spike Array ($9000). This upgrade makes the spike factory shoot 3 times as fast and the Spike Storm abillity to spew out twice as many spikes.
- BOOM!Bloonpop! is probably the tower that deals the most damage per shot without abillities.
- Weapons Research Labratory is incredibly strong combined with a Ray of Doom.
I might add some more things, and if you have any suggestions or if you think the prices and strength of things should be adjusted, let me know in the comments :)