Prince of Darkness

"Reanimate even more powerful Bloon servants to obliterate the enemy and enhances all other Necromancers."

- In-game description

Prince of Darkness (sometimes shortened to POD or PoD) is the final upgrade in Path 3 of the Wizard Monkey in BTD6, and the replacement for the Soulbind upgrade in Version 2.0. The Prince of Darkness can summon undead MOABs and BFBs along with regular undead bloons, and his personal graveyard capacity increases drastically, from 500 to 3000. Undead bloons in the Prince of Darkness's graveyard are also stored for up to 3 rounds instead of 2. In addition, all undead bloons, including his own, get +1 damage and +50% lifespan (lasting 15 seconds instead of 10). Similar to the previous Necromancer upgrade, all the Prince of Darkness's attacks deal +1 damage per 300 undead bloons in his graveyard, up to +10 damage with 3000 bloons stored. Additionally, the Prince of Darkness has massively increased attack speed in addition to the aforementioned benefits. As with Necromancer: Unpopped Army, level 11+ Ezili increases the pierce of reanimated bloons by 50%, which is added before other buffs to pierce are applied, and Guided Magic improves lifespan of all undead bloons by an average of +50%.

On top of all the previous buffs, the Prince of Darkness's main attack becomes 4 times faster, and the dark magic attack inherited from Shimmer becomes 2 times faster.

It costs $20,400 on Easy, $24,000 on Medium, $25,920 on Hard, and $28,800 on Impoppable.

Appearance
The Prince of Darkness is a monkey skeleton donning a black cloak with a purple rim. He sits upon a purple crystal throne decorated with a single green orb on top and 4 black skulls with green eyes. The Prince's eyes have green pupils and completely black sclera (or potentially none), and he wears an unamused or possibly angry expression. In his upgrade icon and portrait, the Prince is eminating green ghosts, and his throne sits on top of a fissure in the ground that glows green.

General Description
Compared to its previous upgrade, the Prince has a higher graveyard storage for its reanimation attacks, in addition to its capability to summon stronger undead bloons. The Prince also gains a buff to its main attack speed to four times faster than the base tower, which can help in taking down enough lesser bloons to summon undead MOAB-class Bloons. Shimmer also gains an attack speed buff to decamo bloons twice as fast.

In addition to its own extra benefits is a buff to all Necromancers, including himself. Each undead bloon gains +1 damage and lasts 5 seconds longer.

Like Necromancers, the Prince of Darkness stores popped bloons in a personal graveyard, local to each Prince of Darkness (if possible to have more than one Prince of Darkness like in Co-Op), and the graveyard can store accumulated bloons popped for up to 3 rounds. Undead bloons are spawned +10% faster for every 100 graveyard units, capped at up to +100% faster with 1000+ graveyard units. All the Prince of Darkness's attacks deal +1 damage per 300 graveyard units stored, up to +10 damage. The personal graveyard stores up to 3000 accumulated pops.

Undead MOABs can deal 40 damage per hit with 20 pierce, expiring after 30 seconds (actually 20 seconds, but the +50% lifespan buff increases that value). Each undead MOAB consumes 20 units from the Prince of Darkness's graveyard. This attack occurs every 3.0s, and only requires the graveyard to have at least 20 units before spawning.

Undead BFBs, on the other hand, deal 100 damage per hit with 50 pierce, but only last 20 seconds (again, actually 13.3 seconds, but increased due to the same lifespan buff). Undead BFBs consume 100 units from the Prince of Darkness's graveyard, and they can only be summoned once the graveyard contains at least 2000 units. This attack occurs every 3.0s, and it replaces the spawning of undead MOABs.

Graveyard Units

 * See also: Undead Bloon

Accumulation
The Prince of Darkness receives graveyard units when bloons are popped within 70 range of the Prince of Darkness (these do not have to be popped by the Prince himself). Each layer popped gives 1 graveyard unit; for instance, popping a MOAB only gives +1 graveyard unit, but popping an entire Rainbow Bloon gives +46 graveyard units. However, from Rounds 81+ when Super Ceramics arrive, popping a Super Ceramic layer gives between 7-13 graveyard units, inclusive, to compensate for the fewer child bloons per Super Ceramic. The Prince of Darkness's graveyard can hold up to 3000 units.

Depletion
Every time the Prince summons undead bloons, it will randomly consume 1-10 graveyard units. 1 to 4 undead bloons are summoned at a time, each consuming the previously mentioned quantities of graveyard space. Each undead bloon has 1 base pierce and gets bonus pierce equivalent to how many graveyard units were consumed.

Undead blimps start spawning after achieving a certain amount of graveyard units. Undead MOABs require at least 20 units in the graveyard before they can spawn, consuming 20 units each, and undead BFBs require at least 2000 units to start spawning, consuming 100 units each. The undead BFBs replace undead MOABs until the Prince's graveyard count drops below 2000.

For every 100 units in the Prince's graveyard, he summons undead bloons +10% faster, up to 100% faster at 1000+ graveyard units. Each undead bloon and undead MOAB also gets 1 bonus damage for every 200 graveyard units (up to +10 at 3000 graveyard units) that the Prince had right before he summoned the bloon. Undead BFBs do not get this bonus damage.

Graveyard units stored in a Prince of Darkness last for up to 3 rounds before being automatically depleted.

Summary
With the massive Version 21.0 buffs to Prince of Darkness, it is an extremely powerful cleanup tower, and actively acts as a guard against the exit. Undead MOABs and undead BFBs can demolish huge groups of weaker bloons with ease, especially normal MOABs and Super Ceramics in late-game. The greatly-enhanced Shimmer attack is also useful for countering the camo properties of DDTs. It becomes extremely powerful with sufficient supporting DPS towers nearby, but without them it becomes extremely weak.

The Prince of Darkness comes massive enhancements to all its attacks: 4x faster bolts, 2x faster shimmers, and +1 damage and +50% lifespan for all undead bloons on screen. The scaling attack speed and damage of all undead bloons becomes even more significant on the Prince of Darkness, for up to +10 damage and +100% faster, alongside up to +10 pierce like all other Necromancers. At maximum strength, the powerful army of undead bloons paired with undead BFBs can obliterate large groups of bloons below ZOMG with almost no trouble, even versus BFBs.

Tips

 * The Prince of Darkness, although super powerful at its maximum power, requires some support in order to become effective on rounds where single-target damage per second is important, especially rounds like round 80, 85, 87, 97, and 100. Adding towers that are effective countermeasures against high-HP singular blimps, such as Maim MOAB or Spike Storm, are helpful.
 * Prince of Darkness can also get overwhelmed with too many ceramic bloons at once, meaning support is recommended for it to beat rounds like round 98.
 * When used in combination with general supporting damage to build up its undead bloon count, Prince of Darkness can fully solo the DDTs on rounds 90, 93, and 95, as well as almost completely solo the Fortified DDTs on Round 99.
 * Letting the majority of the main defense attack close to the Prince of Darkness is helpful so that the Prince of Darkness can generate graveyard count a lot more reliably. Since the Prince of Darkness's actual graveyard collection range is slightly larger than his massive base range (70 range instead of 60), it is important to add supporting towers nearby him for assistance.
 * Use 2-0-5 Prince of Darkness on maps with line of sight issues, like Flooded Valley, but use the 0-2-5 Prince of Darkness to utilize the potentially extremely high damage output that it can deal, since the Prince gets up to +10 damage on all attacks with a full enough graveyard. Note that Wall of Fire will always target the closest area of track, which means the massive range of Prince of Darkness does not affect the Wall of Fire attack's positions whatsoever.
 * Just like Necromancer: Unpopped Army, the Prince of Darkness is best used on single-lane maps, although because of the new Version 21.0 buffs it will always spawn from the exits and aim towards paths where bloons are closest towards the exit.
 * Like the Necromancer, the Prince of Darkness is best used for anti-stalling and is optimized with anti-stalling. If used purely for anti-stalling purposes, place it near the start of the map alongside extra MOAB-class damage support. This will allow the Prince of Darkness to easily gain maximum graveyard capacity to summon many powerful undead MOABs and undead BFBs, for maximum damage output. Otherwise, placing it close to the exit(s) to optimize its cleanup potential in CHIMPS games.
 * Placing Necromancers nearby a Prince of Darkness can actually compete for the same pop, meaning that they can actually steal Prince of Darkness pops. However, having nearby Necromancers isn't always a bad idea because this can make all of them pack a bigger chain reaction against dense bloons.

Trivia

 * The Prince of Darkness is sitting on a throne that does not rotate with the tower's aiming.
 * Before update 2.0, this upgrade used to be Soulbind. The Soulbind upgrade unlocked an ability that allowed the player to bind towers to the Wizard and sacrifice them for extra lives if bloons got through.
 * The graphics for the Soulbind/Prince of Darkness upgrades remained the same through the update; both towers have/had the same graphics.
 * The Wizard moves its hands when attacking and summoning bloons.
 * Note that similar to its predecessor, the Wizard does not have to pop the bloons himself, they simply have to be popped within his presence to become undead.
 * The undead Bloons, MOABs, and BFBs aren't affected by the Big Bloon Option.
 * From Version 11.0 until Version 30.0, due to a massive range buff, Prince of Darkness has more range than Arcane Mastery and their subsequent upgrades.
 * The tower's name might be a reference to a movie of the same name which is about a necromancer.
 * There was a glitch with this tower and Necromancer: Unpopped Army where upon exiting the current game, go to sandbox, pop some bloons and spawn zombies, then go back and start the round, the Necromancer or PoD would spawn the zombies from your sandbox session allowing for easy zombie spawns.
 * This was patched as of Version 18.0. Now the "graveyard" stores all popped bloons from last round, and the amount of bloons sent there will be constant.
 * ISAB posted a couple of videos showcasing the "Prince of Darkness glitch", the latest being the video "Zombie Bloons Are A DISASTER On This Map (Bloons TD 6)", which he used to attempt to beat a certain challenge set on Dark Castle Medium CHIMPS with higher HP Ceramics and higher HP but slower MOAB-class.
 * With the Version 21.0 buffs, one 0-2-5 Prince of Darkness can almost fully solo basically any round on Logs CHIMPS except Round 97 and 100. Additionally, a multitude of 2TC combos with Prince of Darkness were done within two days, with a majority within even a single day: Inferno Ring, Perma Charge, The Anti-Bloon, Pre-Emptive Strike, Carpet of Spikes, MOAB Eliminator, Admiral Brickell, First Strike Capability, MOAB Domination, Churchill, and Avatar of Wrath
 * On the third day, Perma-Spike, Glaive Lord, and Comanche Commander were also additional added as 2TC combos with Prince of Darkness.
 * The description for Prince of Darkness was changed to include buffing all other Necromancers, and has been confirmed on Version 18.0, although the description may have been changed well before then.
 * Within the first day of release of the Dartling Gunner, all Tier 5 Dartling Gunners have 2TC combos with Prince of Darkness.
 * The Version 23.0 nerf to Prince of Darkness was intended by Ninja Kiwi to have been incorporated in the previous update, but they pulled it back due to previously unresolved bugs while attempting to balance it out. The new balance change has made Prince of Darkness more reliable at stockpiling but less capable of maxing out its graveyard damage stacks.