I quite enjoyed the recently concluded Robomi + Robomi: Generations events. The loot wasn’t bad (I believe the Robomi summon is quite valuable because its dispel seems very reliable, and the light/dark SSR weapons are OK for incomplete weapon pools), and Robomi had the best story out of the story events I’ve seen so far (Boots & Blades, Miscolored Memories, Robomi, Robomi: Generations). All things considered, it had some surprises and emotional moments. Robomi: Generations wasn’t particularly special, more like a textbook tokusatsu, but I guess fans of the genre would probably enjoy it.
Dark Giant of the Blue Sea, on the other hand, is what I’d call a step back. More accurately, it’s a blast from the past. The first reference to the event is strip #87 in Gran Blues, which I think means it was something like the fourth earliest story event (Robomi, on the other hand, first showed up in strip #321). While there was more cringe in Boots & Blades’ story, Dark Giant of the Blue Sea might be worse because it is just bland. It’s really straightforward: Sig, a pirate leader, wants to defeat Albacore, a big fish that might be a primal beast. That just about sums it up.
Is the loot any good? The event summon Albacore has a worse aura (leader skill) than Diablo, 20% HP/ATK vs. 10%/30% HP/ATK, and its active skill–a chance to debuff enemies’ double attack rate–is okay, but not a must have. The event weapons offer little value other than skill up fodder (Celeste Claws > Albacore Head).
In my opinion, play until you acquire 300,000 honors or pull an SR harpoon from the drawbox, whichever comes first. This will recruit Sig to your party, who looks like a decently useful SR character. It’s hard to recommend doing much else besides that.