The core idea is timing your new game plus start perfectly from any expedition flag once you've beaten that final encounter. You'll keep all those hard-earned character upgrades and inventory stuff like pictos and lumina, but get ready because everything hits way harder this time around. Those secret achievements though that's where it gets really interesting, especially when tackling bosses with the new modifiers active. Maybe interesting to note that positioning becomes super critical during those enhanced boss fights, particularly when they start mixing up their attack patterns around 50% health.

The smart approach is sticking close to environmental cover during their telegraphed strikes, then punishing their recovery frames - just watch the timing on those new combo extensions. Your old outfits carry over but collecting those ng+ exclusive ones like clea actually ties into some of those hidden achievements. Tip worth remembering is to wrap up any relationship quests or side content beforehand since those reset completely, and you'll want that extra gear for the amped-up difficulty. Getting those secret unlocks often comes down to really precise execution especially during those flying manor challenges where enemy patterns get pretty wild with the difficulty modifiers active.

Some of the trickiest achievements actually involve specific positioning during boss phases, so pay attention to their new move tells - that slight glow before their enhanced attacks is your cue to create space and prep your counter-timing.