V.O.I.D. (BTDi)

The Vicious Omnipotent Interstellar Destroyer is one of the largest bloons ever discovered, first appearing in Bloons Tower Defense i. Its outer layer takes 300 million hits to pop. It also has 16 blue auracrysts, each with 4.5 million health, making its total effective health 372 million.

VOIDs were primarily manufactured as interstellar carriers, capable of holding millions of bloons and traveling great distances across space. They have many powerful engines to make up for their great size, which can accelerate it to relativistic speeds in deep space but aren't very efficient. Their abilities enable them to jump through dimensions, but at the cost of a lot of energy. Because of their massive power consumption, they are often seen draining entire stars to increase their energy reserves, earning them the nickname "Stareater Blimps".

Backstory
After the sixth bloon war, the bloons began equipping blimps with extremely powerful weapons, capable of destroying the monkey defenses rather than just rushing through them. The VOID was built for area damage and equipped with many explosive weapons. Its engines are powerful enough for it to be considered a torchship, which already makes it a weapon of mass destruction, never mind its massive payload of plasma bombs. Even the earliest VOIDs have been known to throw off the orbit of planets with their power.

The dimensional collapse that sparked Bloons i released millions of universes worth of energy, part of which was absorbed by the strongest bloons. The VOIDs gained powerful magical abilities in this process. As if they weren't already bad enough, they gained the ability to teleport as well as several dark magic attacks.

Relativistic Acceleration
Speed increases the longer it is alive. Base speed increases by 10% every 10 seconds.

Dimension Shift
All projectiles pass through it with no effect for 5 seconds, similar to the Phasing property.

Dimension Boost
Charges up for a few seconds before teleporting forward on the track. Distance traveled approximately 10 seconds worth of its normal movement. The rift collapse sends a sideways shockwave that does 1500 damage to any tower in its way.

Engine Blast
Activates its engines, doubling its speed for 10 seconds. The particle streams from its engines deal 800 damage per second to all towers in their path and apply 0.1% Radiation.

Carpet Bomb
Fires out 60 small plasma bombs from its sides in bursts of 20 separated by a few seconds. Each bomb explodes in a 50-pixel radius, inflicting 80 damage and burning towers for 4 seconds.

Cluster Missile
Fires a guided missile at the most powerful tower on the track, which splits into 8 submunitions on impact. Each explosion does 600 damage in a 100-pixel radius and inflicts high Burning damage.

No Survivors
Upon destruction, the core detonates, doing 4500 damage in an 800-pixel radius.

This isn't done yet, I'm adding more stuff to this list

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