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YOUR CHARACTERS
start at level 1 for each class and gain levels quickly. Unlike Commander Shepard, your characters ('kits') in MP come with just 3 powers, plus a passive damage tree and one for Fitness. Much of what makes each kit unique is the particular combination of powers.
At level 20, the top level, you'll have enough points to fill five of those trees, leaving one empty (going, say, 6/6/0/6/6), or nearly filling two or three (6/6/6/5/3, or 6/6/4/4/6).
All of your characters within a given class level together. So when you earn experience as a Turian Soldier, your Human Soldier levels up, too.
When building your character, plan the powers you'd most like. Narida's Build Calculator is invaluable, and there are many guides in Crimson's Build Library.
If you want to try different powers, 6/6/6/5/3 is almost always a decent option, with few exceptions. Skipping a power altogether to max the others works best when you know specifically what you'll use.
As with every game, there are known bugs, and three worth knowing when choosing your builds: don't choose Shockwave Rank 4 Radius, Electric Slash Rank 4 Detonate, or Snap Freeze Rank 6 Tech Combo. More info in my Guide to Guides.
Respeccing a character can be done two ways. There are rare Respec cards in some Packs (you can hold a maximum of 3), or once you reach level 20, you can 'Promote,' resetting all your characters in that class (all your Sentinels, say), to level 1, with unassigned powers. Gaining levels comes quickly.
Your characters also have particular skills for moving and melee. Some can roll to avoid fire, some teleport, some can't roll at all. Their light and heavy melee attacks also have different effects, and taking varying lengths of time, so try them out when you first start a game to get a feel.
Gain more characters (and weapons, and gear and consumables) by buying Packs at the online Store. Start with Recruit Packs until you have many of the common items, then step up to Veteran Packs, and so on. Earn credits by completing games.
STARTING A GAME
First, manage your character. Adjust appearance, then choose powers and weapons; the default weapons aren't necessarily your best options.
Always add Gear once you get some. Always. Under 'Equipment,' there are four options for adding bonuses to your match. Three are consumed during that match - ammo, armor, and weapon bonuses.
Many players save them for harder levels, but they're easy enough to replace with more Recruit Packs (at level 1, when starting).
Gear, though, is not consumed, so there's no reason not to use it each game. You'll need to reset it each time you re-select a character.
Then choose Quick Match and select your options. Bronze is a great way to start, and there's no reason to move to Silver and above until those are fun for you.
In the Lobby screen, you'll see your teammates and can peek at their weapons and Equipment. Teammates have the option to vote to Kick someone there, but it's rarely a problem in lower difficulties. Later, they'll be eyeing your class and your N7 and Challenge Ratings. Personally, I don't put much into any one of those, though I do like to see what players choose for Equipment.
GAME TACTICS
Practice your roll and try out your melee when you first land. You have a few moments before the waves begin.
Move with your teammates. Certain classes do well on their own, especially on Bronze and Silver, but leave that until you know your maps, your enemies, and your teammates. Sticking with your team is rarely wrong.
Avoid enemy bombs and environmental hazards, like the Ball of Doom on Firebase Glacier. I was embarassingly slow to learn this when starting, hoping that cover would save me. It didn't. I tested it. A lot.
Treat Collector Swarms seriously, too. They're small, and net you few points when killing them, so it's easy to view them as simple annoyances, but the delay they cause to power recharge can be deadly. Collectors in general require specific coping tactics, so while learning them, stick with your team.
Be careful when engaging bosses at melee range. After they do one melee attack, with their next strike they can insta-kill you (a 'sync kill,' where the animation syncs you to them and you're unable to move); Banshees can do so without a previous attack, but not while they cast their warp-ball.
When you die, you can press Spacebar to increase the time a teammate has to rez you (you did stick with your team, yes?), but if an enemy stomps on your head in the meantime, it's over, and you're in Spectator Mode until the end of the wave. If you've died far from your team, or if your help is needed instantly, use a Medigel to revive. Better yet, use an Ops Pack before you die to restore your shields and health.
The last of your 3 consumables available in-game is a Cobra Missle Launcher (and like the others, gained through Recruit and other Packs). It's best aimed at the floor by your enemy, and it will kill anything nearby in one shot. Very useful, and often overlooked.
That said, it doesn't necessarily help to use it at the start of a wave, because more bosses will spawn to replace those lost; it's generally best to take out lower-ranking enemies first. And you'll need the skills to take down bosses without them anyway.
The three times a Cobra Missile really help are
- When it saves you or your team from wipeout, like in the last seconds of an overrun LZ or terminal hack.
- When your team is taking a beating and new enemies have stopped spawning.
- When a boss prevents completion of an Objective, below.
- Kill certain targets before a timer runs out
- Fetch and retreive two objects ('pizza')
- Disable 4 devices.
- Escort a drone.
- Hack a terminal (defend an area)
When disabling, you don't speed a timer by helping another player already on the device. You help more by clearing any enemies around them, or if there aren't any, by going hunting. If you stand next to him or her, you'll just draw enemies to that area.
When hacking a terminal or escorting, though, the objective speeds along with more players in the marked area. On higher difficulties, experienced teams will sometimes send one player out to flank and clear enemies, but far more often, teams have trouble when players don't gather by the objective. For these missions, you generally want to get to the terminal area/ drone and stay with it.
Finally, and I'll say this again, for Wave 11, do not run to the Landing Zone in the first moments of the wave.
This must be the single most common beginner mistake, and I've seen it even from experienced players on Gold. Enemies converge on you, and if you camp the LZ, they'll pour on you like rain when you're trying to survive.
For the first minute at least, it's better to go away from the LZ. A good team, on higher difficulties, will clear along the edge, and at a certain time (somewhere around a minute, depending on the terrain and the composition of the team, often later than that) will clear back to the LZ, leaving enemies trailing behind them. If your team isn't doing this, you can still do some of that on your own, staying aware of your teammates and close enough to help. Just don't start by defending the Alamo.
GETTING STRONGER
Packs bought at the Store improve your weapons bit by bit, and that does help. You'll get roughly 15,000 per Bronze run and 30,000 per Silver. While you can earn more on Gold, Silver and Bronze are so fast, they're great places to start - and to stay until you enjoy the other levels.
But the main thing that differentiates great from average players is their understanding of game mechanics. You'll learn where enemies spawn, how they move, how to avoid sync-kills, how to clear around the edges, when to leave bosses for last (usually, at later difficulties, though not always).
There's a complete set of links for game mechanics in the Guide to Guides. See the third post for links to excellent tips on Multiplayer, including Sirian's Tips for the Intermediate Player, like the use of 'soft cover' and 'right-hand advantage' to protect you while shooting an enemy.
In the first post, there's a list of common in-game bugs, so if you find you suddenly can't use your powers or all enemies are invisible, check the resources in the link.
TL;DR
- Play Bronze until you enjoy Silver more. Both are fun.
- Help complete Objectives swiftly.
- Stick with your team, or at the very least, a teammate, while learning the maps.
- Be careful when in melee range of a boss.
- Stay away from the LZ for the first minute of extraction!