Cosmic Monolith Battle

The  is a tough 50-round Special Mission unlocked at Rank 70. It features a hostile Cosmic Monolith at the top of the track, which will passively cast its dark-based spells on your towers. If you fail to beat the Cosmic Monolith by the end of Round 50, it will teleport off-screen and you will get a game over... after a cutscene of several Cosmic Monoliths destroying Grand Monkeyopolis.

Beating this mission for the first time rewards you with 300 Monkey Money and the Cosmic Monolith tower. Beating this mission after the first time rewards you with 200 Monkey Money.

Cosmic Monolith Stats
The Cosmic Monolith featured here has 50,000 HP and can use several spells. This Cosmic Monolith has a 90% evade chance. It only uses spells about once every few rounds at first, but as the Monolith takes damage and as the rounds pass, the spells are used quicker.
 * Antimatter: Deals 40HP dark damage to the target tower, and 5HP damage to all other towers in the radius of a Big One.
 * Pulse: Deals 60HP dark damage to the target tower. May reduce target's damage by 20% for 10 seconds.
 * Pulsar: Used past Round 10. Deals 35HP damage to all towers in a radius 25% larger than a Big One.
 * Cosmic Buff: Boosts evade to 95%, and increases damage by 70%, for 20 seconds.
 * Doomsday: Only used below 10,000HP. Fires a laser, dealing only 2HP dark damage.  A giant fissure will open up, dealing 200HP damage to all towers near the fissure, and 40HP damage to all other towers.  All Bloons on-screen take 1000HP damage.  Cosmic Monolith is healed by 500HP.  40-second cooldown.

The Cosmic Monolith also has many resistances:
 * 85% resistance to fire-based attacks.
 * x2.5 damage from electricity-based attacks.
 * 80% resistance to ice-based attacks.
 * 100% resistance to earth-based attacks.
 * 100% resistance to poison-based attacks.
 * 40% resistance to explosive attacks.
 * 95% resistance to wind-based attacks.
 * x2 damage from water-based attacks.
 * 70% resistance to holy attacks.
 * Healed by dark attacks equal to $$intendeddamage * (1.8+(damagetaken/40000))$$. Does not evade dark-based attacks.
 * 10% resistance to everything else.

Restrictions
There is very little terrain on the track.