Hi-Fi RUSH

After beating the game for the first time you will gain access to the SPECTRA DOORS you probably came across while playing but were locked out of.

There are a total of 8 SPECTRA DOORS in the main levels which contain Combat challenges that range in difficulty.

After completing all of these and returning to the hideout you will now be able to talk to Peppermint and access the SPECTRA HUB ROOM.

This room basically just has another 8 DOORS and 1 DOOR at the end of the room you can't access until you beat the 8 OTHER DOORS and their challenges.

After completing all 8 DOORS you will be able to access the 9TH FINAL DOOR. It contains... After completing it you will get the achievement.

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A D V I C E

The only door that stood out in terms of challenge for me was the last DOOR 16.

It requires you to PERFORM 4 OVERKILL DEFEATS. Which is basically when you call in your friends on a BEAT HIT to finish an enemy which keeps them alive for you to keep comboing but requires your REVERB GAUGE.

Sounds simple but the battle has you start with no REVERB GAUGE and only gives you 8 enemies which spawn in a group of 5 and then 3.

My advice is to use the SHRED COMBO. Which is MASH , this is the best combo for gaining batteries which fills up your REVERB GAUGE. Try using it on the big Samurai so you don't kill the smaller enemies. Try to hit as many ememies as possible with the final BEAT HIT. Any enemy caught in the BEAT HIT explosion drops batteries.

Then you can pretty easily get enough REVERB GAUGE to OVERKILL the smaller enemies. You can use QUICK BEAT HIT + at the same time to activate a BEAT HIT on command and call in your friends to OVERKILL.

Then on the next group of 3 large enemies you can use SHRED and fight normally until they activate their RYTHM PARRY ATTACKS and purposely fail the final blow so you can OVERKILL them as well.

After completing the game there are 16 SPECTRA doors to find. These are challenge rooms that you’ll need to complete, your score doesn’t matter. Half of them are hidden in levels, while the other half are found in the SPECTRA Hub that is unlocked for completing the first 8 challenges. With all 16 challenge rooms completed, a final room in the SPECTRA Hub opens. Head inside and complete the secret ending.

00:00 SPECTRA Door 1 (Level 1)
01:24 SPECTRA Door 2 (Level 2)
03:08 SPECTRA Door 3 (Level 3)
04:34 SPECTRA Door 4 (Level 4)
06:20 SPECTRA Door 5 (Level 5)
07:36 SPECTRA Door 6 (Level 7)
09:40 SPECTRA Door 7 (Level 8)
11:11 SPECTRA Door 8 (Level 10)
14:42 Accessing SPECTRA Hub Room
15:25 SPECTRA Door 9
16:44 SPECTRA Door 10
19:02 SPECTRA Door 11
19:54 SPECTRA Door 12
23:27 SPECTRA Door 13
24:54 SPECTRA Door 14
26:10 SPECTRA Door 15
27:15 SPECTRA Door 16
29:55 SECRET ENDING