It's a great DLC! If you enjoyed the main game then you'll probably enjoy this one too. I would say it's three levels of cut content from the main game. I assume, originally the Time-Lock wasn't designed to come online after you've activated the Sirian plasma generators, but Sam had to turn it on first and this is what the DLC is about. Three levels that take place in the middle of the main story and also introduces the jetpack properly and not just during the final boss fight. As I've mentioned in my main game review, I'm a bit sad about this cut-content-given-back feeling, but overall it's a fun expansion. The levels are unique with some puzzles to solve, but the same awesome gunplay, enemies and secrets as you would expect are here. The Reptiloids are back, you'll have more time with the Sniper Rifle and it adds more to the main story. A bit short, but fun DLC.
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