You feel like the universe is staring you down...
Cosmos is the final Drake Lord, and cannot be summoned unless the other 4 are defeated. He is summoned with The Mirror of The Universe in any biome. He is a Moon Lord-esque entitie in terms of AI. His Mirror is made at an Ancient Manipulator. Upon usage, 1 minute after the items usage, he will appear. He is a dragon with silver scales. This fight is long and hard, so be ready.
Stats
100000 HP
90 Defense
100 Attack (Energy blast)
The Fight
When summoned, instead of having 2 hands and a forehead eye to kill to kill his core, instead you need to kill the 4 Elemental Crystals he summons. When they are summoned, they float around, following you. They are about as big as one of the Celestial Pillars. He summons them 1 at a time, but these Crystals seem familiar...
Stage 1
The first Crystal he summons the light green Crystal of Heaven. It's fairly easy to deal with, as all it does is shoot a green blast at you.
Stats (Crystal of Heaven)
90000 HP
70 Defense
120 Attack (Energy Blast)
Stage 2
The next Crystal he summons is the stone grey Crystal of The Land. It summons a grey serpent that will try to coil you. If the serpent hits you, you will be inflicted with "Slow".
Stats (Earth Serpent)
900 HP
20 Defense
50 Attack
Stats (Crystal of The Land)
90000 HP
80 Defense
0 Attack
Stage 3
He then summons the deep blue Crystal of The Sea. It will summon shoot red, player-seeking sharks.
Stats (Sharks)
100 HP
90 Attack
40 Defense
Stats (Crystal of The Sea)
90000 HP
85 Defense
0 Attack
Stage 4
The last Crystal he summons is the Crystal of Hell, which is a fiery red. It will cast possessed fireballs of all the flame types. They will track the player, but can be destroyed by hitting them with a weapon.
Stats (Crystal of Hell)
90000 HP
90 Defense
95 Attack (Possessed Fireball)
95 Attack (Possessed Frozen Fireball)
90 Attack (Possessed Cursed Fireball)
85 Attack (Possessed Shadow Fireball)
Stage 5
He no longer summons the Crystals, but now fights you himself. You need to hit his chest in order to damage him. He attacks with silver blasts of energy.
Dialog
Upon using his mirror: Skyla... Crag... Syren... Pyro... You killed ALL of them...
5 Seconds before he appears: How about I return the favor?
Stage 1: The wind will rip you apart, limb from limb!
Stage 2: The ground will consume you!
Stage 3: The water will drown you in it's depths!
Stage 4: You should be burning in hell!
Stage 5: Impressive... I'm surprised you made it this far. But you won't last long.
Upon Death: H-How...? Skyla... Crag... Syren... Pyro... I failed you...
Drops
10 Platinum
30-70 Dragon Scales (For special armor)
Dragon Spirit (Expert only)
Facts
The 4 Crystals represent the previous 4 Drake Lords.
His lines for stages 1-4 represent the 4 elements.
An alternate way to defeat this boss is by using Aitherion's Great Scythe when the boss is below 25% HP. When used, the player will swing the scythe to their side, and the scythe will start glowing with a strange aura of light. The player will say "Did you think I wanted to destroy this world by collecting the objects? The truth is far from that. I brought together to summon Him. And like most of the other evils in this world I've summoned, I will slay Him." Cosmos will then reply "Do you honestly believe a mortal can do that? If you fail, you will lose everything you love. Everything you've fought for. Is that really a price worth paying?" The player will reply "Aitherion chose me because he saw that I could and would do it. I'm not backing down now." Cosmos will then reply "Then take this final object. When the time comes, know that I'll be there fighting Him with you." He will then drop the Prismatic Scale and fly away. Unlike most other Drake Lord bosses, his despawn message will say "Cosmos, Drake Lord of The Universe, has pledged loyalty to {Name of Player}, Aitherion's Successor."