Terraria's final update, Journey's End, arrived in May 2020—except its actual final update came out several months later, in October 2020.
Ah, but then «unfinished business» resulted in the Labor of Love update in 2022, something developer Re-Logic said «we needed to do before we could feel fully comfortable moving on.» But then instead of moving on, another «definitely final update» was announced in 2022.
That update, 1.4.5, is currently holding as the final final Terraria update, but only because it's not actually finished yet.
It was supposed to be out in 2023 but that didn't work, and neither did 2024. It's getting there, but the choice was to crunch to make a 2024 release, or to just let it go and get it out sometime in '25, which the studio eventually opted to do. «We are sure that will not be welcome news for many—but we remain committed to being a quality-first studio, so we will take the time necessary for each update to feel 'just right'… and we think that once the update is out, everyone will appreciate that time and care,» Re-Logic's Ted «Loki» Murphy wrote at the time. «Apologies for this one taking so long for sure, but it will be well worth it.» Ah, but there's another, secret reason Re-Logic won't stop working on Terraria: Life itself. «Terraria will never die as long as there is one last final update,» lead developer Andrew 'Redigit' Spinks said on Bluesky (via GamesRadar).
He also revealed his ultimate long-term plan for Terraria, which isn't just to make a really great, unforgettable videogame, but to achieve immortality: «Before I die, I will upload my consciousness to Terraria, there I can troll the players for the rest of eternity.» Hey, it's good to have a goal, although I rather strongly suspect Spinks isn't being entirely serious here.