rip_indra is a level 1500 boss from the 
Second Sea, modeled after the former avatar of admin rip_indra. You face him on a small dedicated island with 100,000 HP and an almost instant respawn of 20 seconds.
How to get it
Talk to 
King Red Head (level 1500 required) in the Second Sea - he teleports you to the small island where rip_indra awaits. You can also reach it by sea, but the journey is very long and not recommended.
How to defeat him
Beware of his mid-life mechanic - outside the puzzle, once his HP drops to half, a black cloud surrounds him and all his health is restored, making it impossible to defeat him without a team. During the puzzle, the same cloud appears but you're teleported to your spawn point and the cinematic plays. Defeating him unlocks a combat scene between rip_indra and King Red Head, plus access to NPC 
Mr. Captain at the 
Green Zone docks.
Our take
An iconic Second Sea boss impossible to defeat solo outside the puzzle - bring a team to get past his regeneration cloud.
rip_indra True Form
Indra Egg
Rip Commander
Rip Legionnaire
rip_return
Bosses
Longma
Luckymaxer
Magma General
Magma General
Megalo Guard
Mob Leader
Orbitus
Order
Red Commander
Red Legionnaire
rip_indra
Saber Expert
Smoke Admiral
Soul Reaper
Stone
Swan
Terrorshark
The Gorilla King
The Saw
Thunder God