Gameplay
Decisions from Mass Effect and Mass Effect 2 will be imported into Mass Effect 3 to keep continuity within the series. Over 1,000 variables will be pulled to shape how players experience the final chapter.[10] Unlike in Mass Effect 2, Commander Shepard will start the game with some powers.[8] The character creator will have more features and hair-styles included than in Mass Effect 2 and players will be able to change class when importing their character. There will be no origin-story comic for new players to help them make quick decisions without having to play the previous two games. Upon finishing the game, there will be a New Game+ option that allows players to continue playing after the main story ends or start again with their finished Shepard and collect items they missed the first time around. If players achieved a love interest in both Mass Effect and Mass Effect 2, then there will be two love interests vying for their Shepard's attention in Mass Effect 3.This "love triangle" will be resolved by the end of the game.
Locations in Mass Effect 3 will include the salarian homeworld Sur'Kesh, the asari homeworld Thessia, the turian homeworld Palaven, the quarian homeworld Rannoch, a human mining base in a Martian crater, and a giant city on Earth representing the combination of Seattle and Vancouver. Players will also return to Tuchanka - the krogan homeworld - and Illium.
Mass Effect 3 will have more RPG elements than Mass Effect 2. For the first time in the series, players will have skills that start along a single path and then splinter into two branches where they can select only one upgrade or the other along a sequence of possibilities. Players will also be able to customize their weapons with different scopes, mods, barrels and ammo types.The game will include mini-games (although planet scanning is unlikely to return) and Hammerhead and Mako missions.
As of August 23, 2011, BioWare has confirmed the return of previous characters Illusive Man, Garrus Vakarian, Liara T'Soni, Kaidan Alenko or Ashley Williams, Legion, Tali'Zorah, Urdnot Wrex, Jack, Mordin Solus, Ambassador Udina, Captain Anderson, Zaeed Massani, Kelly Chambers, Thane Krios, Jacob Taylor and Miranda Lawson from Mass Effect and Mass Effect 2. Some characters will not return if they were killed at any point during the previous games. The number of characters available as squad mates will be smaller than in Mass Effect 2 for the purposes of deeper relationships and more interesting interplay, including same-sex relationships for both male and female Shepards. BioWare has also confirmed a new character called James Vega.
Combat
Combat in Mass Effect 3 has been radically changed and refined from Mass Effect 2, and further emphasis has been put on third-person shooter aspects to make the game more commercially viable.[24] In a preview for IGN, editor Arthur Gies went so far as to say the game "plays like a shooter" and that "combat-wise, Mass Effect 3 is in an entirely different space" from the first two games.
The series' cover system has been improved so players no longer need to slide into cover and then hop over objects. Players will have more options for moving around the battlefield, including a refined sprint capability, combat rolling, and the use of climbable ladders. Players can also blindfire their weapons from covered positions, and have opportunities to shoot selected armor pieces and limbs off enemies.Moving and shooting, a previously "suicidal maneuver" in Mass Effect 2, will finally be a viable option because of a revised melee system. Players will be able to execute formidable punches and attacks, and instant melee kills will be introduced specific to each class; for example, by holding down the melee button, a soldier Shepard will deliver a killing blow with a tech-blade in his/her wrist armor. Actual, round, conventional grenades will also be available.
Mass Effect 3 plans to be the most difficult in the series, with increased artificial intelligence to challenge players and increase the sense of reward. Enemies no longer act as individuals as they did in the previous games, instead fighting and supporting each other in units. Enemies include 15-foot tall Cerberus mechs, assault troopers, and ninja-style shock troops, as well as Reaperized husks of all races and Reaper ships ranging from 500m to 2km long. Some changes will be made to already-existing class types; for example, Engineers will be able to build turrets.