[To unlock Death by Disco], you must throw a groovitron at every single enemy in the game.
To acquire this bronze trophy (which is insultingly low in the PlayStation tiering), you must throw a groovitron at every single enemy in the game. You may be asking just what that is - well, it's a weapon that causes foes to lose control over themselves, thrusting them into uncontrollable dancing. Think the monkey bombs in Call of Duty, but the zombies end up boogying before being blown sky-high.
Sure, the actual use of the weapon is entertaining, as it always has been, but the last three Ratchet & Clank titles have all had achievements similar to this one, in that you must utilise a weapon on every single enemy in the game, but the issue is that tracking of these trophies gets a little murky when delving into NG+.
When perusing the internet, particularly Reddit, in the hopes of discovering just why this trophy wasn't clocking, I was bombarded with conflicting information. The one key detail that stood out was that the achievement was supposedly meant to carry over your progress from NG to NG+, but in my case, it clicked on the final boss, Dr. Nefarious, even though I'd thrown it at him in every single one of my playthroughs.
So, what went wrong? Well, again, I jumped to Reddit, this time with my own post instead of rummaging through ancient, second-hand info with the comments locked. Apparently, it doesn't carry over from NG+ to other NG+'s, which is a little bit of a head scratch as that means, for those who don't look online or end up misinformed (as I was), you can end up running through Ratchet & Clank over and over and over to no avail, which seems to make this the last trophy that most people get.
The feeling of satisfaction of getting this little dinger of a dopamine fix was ruined by tedious runs, especially with the low replay value of the Clank sections which significantly slow down pacing (seriously, Insomniac, please patch in a skip option for these in NG+). Instead of being overjoyed by getting the Ratchet & Clank PS4 platinum, I was met with a feeling of relief in the fact that I could finally take the disc out of my console to leap into something less horrifying.
How did I get it in the end, after my near-endless struggle? Well, I simply enabled infinite ammo and health and ran through the game, spamming the groovitron, only killing enemies that I had to in order to progress. Apparently, this is how a lot of people got the trophy, or at least according to internet forums.
Related: Review: Ratchet & Clank (2016)
Here's to the next Ratchet & Clank, my favourite game series, avoiding a trophy such as this one - they aren't fun, and just end up resulting in you having an entire playthrough dedicated to a single, bronze achievement.
I feel your pain.