Well this is an excellent game by Bioware. Released on 26th January 2010, Mass Effect 2 has a gripping storyline and gameplay.
You start with customizing your character and choose a class for developing his/her skills as you progress through the game. The character of your hero can be built as a cool(paragon tilt) or aggressive(renegade) nature or a balance of two depending upon what dialogues you choose during gameplay while interacting with other characters or NPCs. You can choose a class for your character in accordance to the powers you wish to have or develop in the game. Available classes are engineer, infiltrator, soldier, adept, vanguard and sentinel. Broadly speaking, engineers have powers to create fighting or defensive drones to aid in combat and can also take control of enemy mechanical units. Infiltrators can disappear for a short time and can gain tactical advantage over enemies. Soldiers can use a variety of weapons that other classes can’t. Biotics like Adept and Vanguards rely on powerful physical attacks to destroy enemies. Sentinals have good armour protection.
Your hero's last name is commander Shepard who dies in a previous mission and resurrected by a powerful terrorist organization called "Cerberus" lead by the mysterious "Illusive Man". The Illusive Man reminds me of the "G-Man" of Half-Life series with similar shiny blue eyes who plays a similar role in Half-Life. The Illusive Man persuades you to work for their organization in interests of humanity and investigate the causes of disappearing human colonies in space.
Initially you are accompanied by two squad mates Jacob and Miranda. More are added as you complete missions. However, for any mission you can't have more than 2 squad mates so have to choose as per your preferences. You have access to various types of weapons ranging from pistols to grenade launchers or powerful alien weapons. You can upgrade these weapons by collecting various resources by scanning planets in the galactic view of the game. This adds another dimension to the gameplay.
The game also teases you with some puzzles which you need to solve in order to open doors or gain money bonuses or resources for buying weapons and upgrades.
Throughout the game there are many side quests you can take in order to increase your character's skill and experience. If you feel bored of fighting and shooting you can wander around various places and have conversations with other characters.
Primary villains in the game are an alien race called “the collectors” and their boss known as “Harbinger”. The basic appearance of this alien race especially Harbinger resembles to that of a fly. I didn’t find this as an impressive character at all. Also Harbinger can take remote control of other collector beings(just like in the movie “the matrix” agents can take control of the bodies of other people). So no surprise there. However, there is something impressive in the last mission of the game. I’ll not talk about it or it’ll be a spoiler indeed for those who’ve not played the game yet.
A distinctive characteristic of this game is that it focuses on human social and personal behaviour and allows you to experience the same through your character. You may have to make choices that would shape up your character's personality.
The game will put you in some scenarios in which you'll have to make hard choices.
Mass Effect 2 is a great game for beginners as well as experienced RPG gamers. It is a radical combination of action and good storyline. A great entertainer.