
It draws power from the reactor, which is why it attempts to stop Artyom from activating it. It has an amoeba pore and several giant tentacles used in killing anyone trying to separate it from the reactor. In the video game, the biomass is a giant biological mass on top of the reactor in D6, found in the Biomass level. And maybe Satan himself is waiting for us up there.

Those who have not invested in the seasons pass would do well to pass up on the second and third DLC installments unless they are die-hard fans of the combat and/or want an opportunity to have a closer look at the various mutants and characters found in the main story.If hell exists, I think we've found it. The final DLC installment promises more story driven missions that focus on characters from the game's main story, so hopefully they finish strong. While it is refreshing to have DLC that doesn't take the shape of multiplayer map-packs, it is frustrating that 4A only occasionally exhibit the same talent that made Last Light such a compelling adventure. This is a great level that begs the question, why aren't 4A making more of the DLC like this? The spiders were the most interesting new monsters in Last Light, requiring you to shine your flashlight on them before they reveal their soft bellies, and they have lost none of their edge here. Eventually you come across some weapons, and you must fight your way out of the spiders’ lair. This 30-minute mission sees you initially without any weapon, trying to find a way out of the complex while spiders scuttle about all around you. This mission, simply labeled "Spiders," sees you waking up in the bottom of a huge spider infested missile silo with no weapons and no surviving companions. There is one glimmer of hope amidst all of this unfulfilling DLC, and it comes in the form of a 'bonus' mission attached to the Developer Pack. There is some glitchyness to the Arena as monsters clip through objects, although it is interesting to see the outcome of unlikely scenarios like a Shrimp and a Ranger fighting a pack of Watchmen mutants.

If you wish, you can go into the Arena and fight them yourself. The Arena is the most interesting aspect of the Developer Pack, allowing you to pit any combination of humans and mutants against each other for your entertainment. The shooting range lets you try out all the different weapons and attachments in the game against a variety of targets that you choose from a panel, including undead soldiers that roam around and shine flashlights into your eyes. The developer pack consists of a museum where you can look at the different mutants and character models found in Metro Last Light, as well as a shooting range and an arena.

The third piece of DLC is a bit of a surprise, going by the name the "Developer Pack." This is a more interesting addition, although it feels like the kind of thing you might expect to find in a digital collector's edition of the game. If you invested in the seasons pass you might as well have a look, but otherwise I wouldn't bother paying for this lukewarm addition to the game. You move between combat arenas at a decent pace which helps keeps things reasonably fresh, and leader boards exist if you feel the need to be competitive. There is some enjoyment to be found here thanks to Metro Last Light's excellent combat model, but it is also disappointing that the developers couldn't think of more interesting ways to contextualize it. As you progress, you gain access to better weapons but also fight more numerous and tougher enemies. You are a wounded Ranger placed in a combat-simulation where you must fight up a tower against increasingly difficult waves of both humans and mutants. The Tower Pack is the second of four scheduled DLC's to launch, and is essentially Metro's take on horde mode.
