Asmodeus

Description
Asmodeus is known to be the mastermind behind any form of demonic invasion, sometimes even Rahovart falls in line.

This is a boss mob that is usually summoned via a Boss Event using an Asmodeus Altar. This boss has 3 Battle Phases.

Quick Tacts: Don't Fly, stay aware of it's Gatling Gun under it's Platform.

Phase 1: Be careful about Trites, watch out for the Devilstar Burst.

Phase 2: Kill Astaroths, as they grant a Shield to Asmodeus, making it invincible until the Astaroths are killed.

Phase 3: Kill Cacodemons, before too many spawn, also watch out for the Astaroths, which can heal it on this Phase.

Arena
When spawned, Asmodeus spawns a massive enormous arena around itself to fight the player. This arena is made out of numerous blocks, including Netherack. The walls of the arena are studded with pillars with flames adorning the top of each of them. However, if you put yourself in a sticky situation, then it is good to have a flying mount to fly over the walls as they do not trap the player in the arena, and therefore, can be escaped.

A handy trick to do is to spawn the boss near the bedrock layer of the nether, so that when it actually spawns in, it not only breaks the bedrock but also prevents Asmodeus from destroying the nether.

Watch out though, as mobs not related to Asmodeus can also spawn here, such as zombie pigmen!

All Phases:
Asmodeus has a deadly demonic gatling gun mounted under it's platform, avoid this at all costs as it will strip your buffs! It will fire for a few seconds before overheating for around 10 seconds (smoke will come from the gun), this may be your time to strike! Asmodeus will jump around it's arena in pursuit of it's current primary target (usually the last player to attack it), there is no escape! Any players that are too high up (flying) will be bombarded with a massive swarm of Nether Souls so stay low.

Phase 1 (100-60% Health)
Summons Trites which have a nasty bite that causes wither. Every 10 seconds or so Asmodeus will unleash a circular burst of Devilstar blasts outwards.

Phase 2 (60-20% Health)
Summons giant Astaroth which will power a shield making Asmodeus invulnerable, these must be defeated in order to damage Asmodeus. Remember that Astaroth will explode into a swarm of Trites on death!

Phase 3 (20-0% Health)
Constantly summons Astaroth at a slow rate which will heal Asmodeus if it is below 20% health. Constantly summons Cacodemons, too many can be overwhelming so keep their numbers under control.

Trivia
Asmodeus's mob event theme is a part of a remix of the Phobos Anomaly theme.
 * Asmodeus is a direct reference to the Spider Mastermind from the Doom series.