How to unlock golden mom fluck (felicitoad) hp?

Push it to the wall to unlock hp. ^_^

 

here is full guide: (lv.150-205, all dps, anyone who have ability to tumble, flinch, stun, and stop it)
1.)aggro holder (no need for tank) take a lead and push it until it cast 3~5 times shark wave
1.1) attacker don't stand/go near to it yet because it can summon the spike close to it (say hello to freaking time killer)
1.2) hp unlocked! do any kind of stun/tumble/flinch or even stop to stop it move and you can go to kill it
2.) hp<50%-80% it will change it pattern when it got pushed (shark wave and meteor), all non aggro holder stay back on the edge and try to get a same position
3.) hp<25%-75% it will spawn spike frequently, so aggro holder need to timing when he should got knock back or not (it will help you with spike placement)
4.) don't worry, if it hp unlocked, it won't attack you

problem to all people who read this:
UNSTABLE INTERNET CONNECTION will make this boss harder (like me who finished ultimate difficulty on 1hr) or you will end up like this