First-person shooters are a dime-a-dozen these days. We see a new Call of Duty every year, new IP’s challenge the shooter champions, and even old favorites get remakes. For many titles, multiplayer has been the determinant of whether the game is successful or not. Each multiplayer mode has its own pros and cons and are backed by obsessive, fire-spewing fanboys praising their favorites and condemning rival titles. So, how are you supposed to know which ones are actually good?

Well, we’ve put our heads together and gathered up our ten favorite shooters that still hold up by today’s standards. These don’t have to be the latest in the franchise but should represent the best experience for a series. So, without further ado, here are our must-play FPS games.

You might not be able to shoot other players competitively (like most other games on this list), but that doesn’t mean that Borderlands 2 is any less of an amazing multiplayer experience. Cooperation is the key to surviving the dangers of the Wasteland, and playing Borderlands 2 with a full, four player party is the best way to play Gearbox’s RPG-style shooter.

Gather your crew of treasure hunting badasses, including the grizzled Commando, deadly ninja, psychic Siren, and the dual machine gun-wielding Gunzerker and blast holes in bandits, monsters, and evil masterminds. But you won’t just be shooting things--you’ll also be hunting down and collecting piles upon piles of loot to find more powerful weapons and items. With addictive looting, some insane but memorable characters, and even more customization options than the original, Borderlands 2 is everything you want in a co-op shooter.

Quake III Arena is one the most hardcore FPS of all time, demanding precision from every part of your cortex. You’ll need divine accuracy and twitch reflexes to even dream of hitting a Railgun shot, and mastering the fine art of rocketjumping and bunny-hopping around the map will make you feel like Speedy Gonzales as you zoom around. But those skills are only half the battle; the other half relies on your spatial reasoning, how well you know an arena's layout, and reaching the chess-like higher-level thinking required to truly know what your opponent will do next.

With that in mind, we were delighted when id Software announced the conversion of their most celebrated multiplayer FPS to a browser-based, free-to-play game. Despite the removal of gib-and-guts gore, this 13-year-old game still stands tall thanks to its timeless gameplay and the addition of intelligent matchmaking. We can only think of one other arena shooter that’s closer to our hearts…

It was a close fight between the original UT and the 2004 installment, but we chose 2000’s Game of the Year Edition for its nostalgic resonance and emphasis on blazing-fast, close-quarters deathmatches. (Also, it has the Unreal series’ best rocket launcher, which could fire six missiles or grenades at a time.) Whether you’re playing against the startlingly-smart AI bots or hosting a LAN with some like-minded buddies who don’t mind an old-school FPS, you’ll find that this white-knuckle shooter holds up after all this time. Quake III may have the edge in terms of competitiveness, but UT takes the retro crown for its sheer fun factor.

With some of the all-time best FPS maps, like the low-gravity Morpheus or CTF classic Facing Worlds, Epic Games crafted arenas that perfect every twist and turn of a gripping shootout, be it team-based or free-for-all. The weapons are equally excellent, offering wildly different functions between primary and secondary firing. Our favorites include the smiley-faced Flak Cannon and the now-legendary Shock Rifle combo shot.

Other shooters' multiplayer matches are dwarfed by the sheer number of players Planetside 2 supports. Think the Battlefield’s 64-player matches are intense? Imagine driving a tank into battle with dozens of vehicles at your back, aerial battles overhead, and infantry skirmishes all around you--and every single thing is controlled by actual players.

Rather than give players menial objectives like capturing flags or focusing on the repetitive task of setting bombs to blow up miscellaneous military boxes, Planetside 2 tasks your empire with conquering entire continents. Hoof it on foot, hop into a vehicle, join a squad, or be a lone wolf. You can do all of the above in the intense, large-scale conflict. If you’re looking for a shooter that makes you feel like you are in the middle of a war, Planetside 2 is right on the money.

Battlefield 3 might not have started off as the best example of a Battlefield title when it first released, but the third installment in the series has been coming into its own with its multiple DLC packs and expansive progression features. BF3 drops you on the battlefield in up to 64 player matches (on PC, 32 on consoles) and gives you free reign over vehicles and highly customizable player classes.

With the additional DLC options, players have many more options to explore. Are you a big fan of running people down with a tank? The Armored Kill expansion is right up your alley. What if you want more fast-paced action like Call of Duty? The smaller Close Quarters maps turn the action up a notch and give you more practice and give you more practice for up close and personal encounters. It may cost a bit more to drop the dough for the additional content, but the full package makes this the ultimate Battlefield experience.

Since the dawn of the FPS, mankind has endeavored to blow zombie brains out the back's of digitized zombie skulls. Eventually it seemed that gamers would tire of murdering undead fiend after undead fiend, but leave it to Valve to find a new way to make it interesting again: four player co-op multiplayer, and let the people play as zombies.

Left 4 Dead 2 built on basics established by the original L4D, introducing new playable infected types, melee weapons and a bold new New Orleans setting. But most importantly, it kept an emphasis on survival horror, forcing players to make split second life or death decisions. Who gets that last health pack? Do we go back for that injured teammate, or make a desperate three man sprint for the exit? The choice, unfortunately, is yours.

Treyarch did a bit more than change the setting, add a few guns, and mix up the Killstreaks in their latest release. Class customization has gotten an overhaul in Call of Duty: Black Ops II with the “Pick 10” system, allowing players to diversify their loadouts like never before. Black Ops 2’s multiplayer is one of the most addictive competitive shooters out there. With dozens of weapons, attachments, equipment, and perks to unlock, you’ll be playing for hours on end, fragging players online to up your kill to death ratio, unlock the next perk, or earn your next weapon camo.

The fun doesn’t stop at the multiplayer mode; the Zombies’ expanded Tranzit and Grief modes offer plenty of new ways to experience the undead apocalypse. Tranzit gives you access to the biggest map in Zombies history, with interconnected locations joined by a bus route, and plenty of hidden items and secret paths to find as you explore. Grief pits player against player in a four-versus-four survive-off, in which any method you use to get the other team killed is fair game. Looking for addictive multiplayer, challenging co-op, and incredibly balanced features? Black Ops II has it all.

Halo 4’s multiplayer modes maintain the same competitive feel that propelled the series to astronomical success, but also make improvements to the gameplay to create the most modern and enjoyable Halo yet. Spartans can now sprint, carry custom loadouts straight into battle, and even earn rewarding Ordinance Drops (similar to Call of Duty's Killstreak rewards). A variety of awesome new weapons have been added as well, thanks to the inclusion of the energy-based Promethean soldiers seen throughout the thrilling campaign.

But standard multiplayer isn't the only way to get some frag time with friends; Halo 4's co-op mode, Spartan Ops, offers some of the most ambitious features in recent shooter history. Players in groups of up to four can complete story-based missions, battling tough Covenant and Promethean foes. What really makes it unique, though, is that Spartan Ops is updated weekly, so you’ll have plenty of challenges to overcome with your buddies for a long, long time.

Counter Strike is the granddaddy of online shooters. So many popular mods and game modes have been birthed from the old-school Half-Life mod. Some newer shooters are only now adding modes similar to CS's Gun Game mod and many others are still trying to capture the essence of what Counter-Strike had. Not only was it well ahead of its time, it is still enjoyed by hundreds of thousands of players today.

To Counter-Strike purists, it still might be preferable to stay out of the source engine, but to do so means missing out on those enhanced visuals from the early 2000s, the fancy ragdoll physics and one of the best CS maps in existence, Office. So, naturally, we decided on the title's updated version.

Why is Team Fortress 2 the ultimate online FPS experience? You mean besides the fact that it's a steadily updated (on the PC, at least), viciously stylish, utterly outlandish shooter you can start playing for the no-money price of free?

Other than the pursuit of more hats, what makes TF 2 so damn playable over and over again? Its oh-so-varied class-based gameplay. Each class has such a distinct role it's like playing an entirely different game. The rocket jumping soldier smacks of Quake 3, the Scout's double jump reminds us of the original Unreal Tournament, and the Medic is like the bizarre Ghostbusters game we'll never have. Enough reasons for ya?

Now you know what our must-play shooters are, but we couldn’t cover all of them – there are a ton of shooters out there after all. Let us know what we missed. What is your favorite shooter to play right now? Got a reason why Battlefield 3 should have made the list? What are your top ten FPS? Sound off in the comments below.