The plot is simply this: a knight, a pirate, a scientist, and a baron travel across the universe, searching for the source of imagination; they inevitably come across a perfectly cubic planet, and land on it. This source of imagination could make any idea come to life...
So the Baron, after going mad on the journey, creates the Maelstrom, a threatening chaotic force. This turns against him and drags him into the source of imagination, where he presumably was absorbed. The source turns dark and is eventually plugged up with the remains of their ship, exploding the planet into fragments.
The remaining crew eventually call upon the help of every available person in the Universe to help ward off the Maelstrom's dark minions, the Stromlings.
In August 2011, the game partially became free-to-play (the first two zones were free for all, with the rest only available to subscribers), but the change apparently failed to attract sufficient amounts of new subscribers, so LEGO ended LEGO Universe on January 31, 2012.
This game contains examples of:
- All There in the Manual: The backstory is detailed on the website, in special missions.
- Allegedly Free Game: Eventually it comes to a point after you've gotten your own property to build on, that you have to be a Member to continue with the storyline and unlock other worlds and missions.
- Abnormal Ammo: The Venture League (one of the in-game factions) is guilty of this trope. Specifically, their Buccaneer class. Rank 1 shoots a trident from it's pistol. Nothing too abnormal about that... But when you get to Rank 2, the pistol shoots a fish. Somewhat fishy, but... Wait! Rank 3 launches a SHARK!
- April Fools' Day: Three news articles were published on the LEGO Universe website on April 1, 2011. One revealed that Bob was actually The Mole; one was a preview of an upcoming "Red Brick" pet that was just a standard 2x4 LEGO brick; and one was showcasing a property where players had to find a brick... which was the only object on the entire property.
- A Taste of Power: Two missions added in the "Power of the Nexus Force" update temporarily give new players special armor that has roughly the power of level 2 faction equipment and 4 extra hearts.
- Big Bad: The Darkitect, who is actually the former Baron Typhonus.
- Broken Aesop: As shown in the intro movie, the lesson to be learned from Baron Typhonus's mistake is that chaos has no master, and the Baron was foolish for thinking that he could control it. But then, it turns out that the Maelstrom is controlled by an entity known as the Darkitect, who happens to be none other than Baron Typhonus himself.
- Bullet Time: In the intro, a couple of shots have this when characters build things.
- Clothes Make the Superman: Your abilities depend on what clothes you wear, in fact due to faction gear (usually the most powerful) being earned through defeating enemies it acts as a pseudo-level system.
- The Corruption: The Maelstrom. All of the Stromlings in Avant Gardens? They were researchers.
- Collection Sidequest: Oh, so very much. Every area in the game has ten (or more) hidden flags to find, and there are more than a dozen "find the hidden chests/compasses/whatever" missions.
- Cosmetic Award: The Vailient capes are only available to those who have hit the current level cap of 40 and are very expensive but only have the powers and defense bonuses of normal level 3 shoulder gear which can be bought earlier and cheaper.
- Dark Action Girl: The current leader of the Paradox Faction, Vanda Darkflame. Apparently stubborn and uncaring of whatever impression her methods give, though that's probably a given in her position.
- Dark Is Not Evil: The Paradox faction uses Maelstrom-based powers, but is fighting to save Imagination like everyone else.
- Death Is Cheap: Exploited- Since everyone is literally made From lego, the dev team decided to include a "smash" button, which allows the player to fall apart and re-spawn at a safer area. This makes for a quicker escape plan and a smart way out of glitched areas.
- The Engineer: One of the faction specialties of the Assembly faction.
- Flunky Boss:
- The three Maelstrom Dragons of Forbidden Valley - Burnshout, Torchblight, and Blastbreath - are aided by a fourth Maelstrom Dragon who spawns Dark Ronin at regular intervals.
- The Maelstrom Spider Queen summons some of her Dark Spiderling offspring at two points during the battle.
- With the exception of Roo Morgg and Butterscorch, any Crux Prime boss could qualify, as they spawn in the battlefield amongst many of their lesser minions.
- Frakjaw spawns several waves of Skulkin enemies to battle against you during his battle.
- Giant Spider: The Maelstrom Spiders, including the Spider Boss and Spider Queen. Their offspring, the smaller but still huge enemies known as Dark Spiderlings, could qualify as well.
- Gone Horribly Right: The Baron wanted to find the essence of pure imagination, and prove that it didn't have limits. What he ended up creating was the Maelstrom, a force of chaos without limits.
- Guide Dang It!: Every single mission on the website.
- The Heartless: The Stromlings.
- Hoist by His Own Petard: Or rather "Dragged by his own Spider Boss".
- The whole point of the Paradox Faction is to defeat the Maelstrom with its own energy.
- Imagination Destroyer: The LEGO Universe thrives on Imagination, a mythical element that is needed to build and create (which, for a world Built with LEGO, is naturally pretty important). The villain is the Maelstrom, a force of chaos and destruction that serves as the antithesis of Imagination. The Maelstrom was created when Baron Typhonus corrupted the Imagination Nexus, and now it seeks to corrupt or extinguish the remaining Imagination in the universe.
- Intentional Engrish for Funny: When the Venture Explorer's computers interpret a coded Maelstrom message, it is mistranslated as "All your base are belong to me!"
- Kick the Dog: An absolutely brutal example; upon the Maelstrom's creation, the first thing the Spider Boss did was stomp on and destroy a Robot Dog. Thankfully, it is later reconstructed.
- Non-Lethal K.O.: When your character runs out of health, they get smashed and rebuild at a safe spot. Justified because, well, you're playing as a Minifigure, and Minifigs can just be put back together again.
- Ninja Pirate Zombie Robot: Ninjas, racers, jungle explorers, pirates, robots, cowboys knights, and spacemen have all been seen to interact. A character's outfit could be a mix of all of these, and more.
- Order Versus Chaos: More like Imagination vs Chaos. Or Creation vs. Destruction, if you prefer.
- Our Dragons Are Different: While there are the typical destructive, evil dragons in the game (which are composed of the evil Maelstrom), it is possible to find and tame a smaller, and nicer dragon as a pet.
- Preorder Bonus: Preordering the game would have gotten you a Minifig wearing Nexus Astronaut Uniform, this same costume can be gotten in game by redeeming a code that would have also come with it.
- Also, everytime you update your subscription a in-game bonus is given, with longer subscriptions giving better awards.
- Product Placement: There is an entire world themed around the Ninjago line of LEGO Products. You can actually learn the Ninjago art of Spinjitzu there, and in general it's actually a pretty fleshed out place, with more missions available than most areas.
- Reference Overdosed: So many references to internet memes. For example, Three Wolf Moon.
- Or here's another one: in the Return to the Venture Explorer mission where you need to gather data from multiple computers (whilst dodging considerably tough enemies), when you complete it, it says "All your base are belong to me."
- One mission is called "Respect My Authority."
- Spacetime Eater: The Maelstrom.
- Vendor Trash: Gems are completely worthless to players, but they can be sold to vendors. Depending on the color of the gem, you can receive anywhere from a measly 10 coins to a grand 50,000 coins by selling these gems.
- Your Reward Is Clothes: Some of the time, there are rewards for achievements that make working towards them worth it, but the rest are either purely cosmetic, don't have any stat boosts (or barely any useful ones by the time), or are ugly.