"ADAM twists the genes, the body, the mind... even the soul. In desperation I turned to ADAM's most innocent victims, the Little Sisters. With you as their protector, they may put a stop to this madness."
The Protector Trials is the first singleplayer DLC for BioShock 2. The Protector Trials are offered on XBL for 400 MS Points and on PSN for $4.99, and became available on August 3, 2010. Initially, the DLC was only released for Xbox and PS3, but after a large community outcry from PC players the development team resumed production and estimated that it would be released by December 2010 for free.[1][2] The PC version of the DLC was finally released on the 14th March, 2011.[3]
Unlike the main story of BioShock 2, the player does not take the role of Subject Delta but controls another Alpha Series taken out of hibernation by Brigid Tenenbaum just before the events of BioShock 2. She wants the Alpha Series to take ADAM away from Sofia Lamb in an attempt to foil her plans.[4]
Each challenge requires the player to protect a Little Sister while she drains ADAM from a corpse using a specific set of weapons, Plasmids and Gene Tonics unique to every trial. Every location has three trials which can earn the player one, two or three stars for completing them, with a corresponding difficulty level. Earning stars unlocks new trials for the player to complete.
In addition to receiving stars, the player receives a grade showing how well they accomplished the trial. The more ADAM the player's Little Sister accrued at the end of the trial, the higher their grade. During the trial, the Little Sister will also have an ADAM multiplier: the longer she drains ADAM without being interrupted, the more of it she drains at a time, capping at x4. If the Little Sister is attacked her multiplier will decrease until the player saves her, also reducing the total amount of ADAM gained during the process.
For strategies for specific trials, see the individual level articles.
Each trial lasts for around four minutes, which is much longer than any gathering session in the main game. Be ready for a prolonged battle.
Among all enemies, only Thuggish Splicers, Leadhead Splicers and Spider Splicers would disrupt the Little Sister, and hence affect the amount of ADAM a player can obtain; all other types of enemies simply aim at the player and fight to their death. Arguably, those weaker enemies should be a higher priority.
In this DLC, the player instantly gains cash after killing an enemy, and enemy corpses are not lootable, therefore there is no need to move around the map rather than stay in a more secure area, or even worry about shattering an enemy because they yield no loot anyway.
Hack all vending machines (and Turrets in some trials) before starting to gather for obvious reasons. As for Health Stations, the player can decide whether to hack or destroy them. Hacking Health Stations not only allows the player to heal at a lower price, but also turns the stations into deadly traps, as all enemies trying to heal will be instantly killed. However, destroying Health Stations would give the player extra First Aid Kits to start the battle.
If traps (such as Trap Rivets or Cyclone Trap) are available, the player should deploy traps near the Little Sister at all times, since enemies can approach her quickly and without any warnings. Proximity Mines are the best choices of traps, as they can defeat most enemies instantly, and require a short amount of time and a low level of skills to set up. Charging a Cyclone Trap with Electro Bolt or Incinerate! is also a good alternative.
Trap Rivets and Trap Spears, on the other hand, are harder to master and may not kill an enemies instantly, making them less practical than the Proximity Mines as traps. However, they are less expensive and can be shot at a target directly which deals a decent amount of damage, especially when one scores a headshot.
Decoy can distract enemies from the player, but cannot distract them from the Little Sister, therefore it cannot eliminate the use of traps.
Despite the research system being absent in this DLC, the Drill Dash ability is available and is the key to success in some trials.
Obtaining all stars, which means simply completing all the basic trials regardless of grades, will unlock the Master Protector Tonic in the Minerva's Den DLC. That Tonic can be acquired at any Gatherer's Gardens in the Minerva's Den DLC without any in-game cost.