Change your settings
It can be difficult to keep up with everything that happens during a fight, but it's not your fault. Marvel's Avengers triggers screen shake and other effects up to 11 by default. If you find the game disorienting, go to the settings menu, reduce screen shake, and adjust other camera options as you wish. You can also change the sensitivity and targeting aid to aim to help you land a little easier.
Focus on ranged enemies first
The Avengers' biggest threat isn't Thanos or MODOK or even Galactus. No, ranged enemies are the real danger. Drones, turrets, and flying enemies can take you down quickly in just one or two hits, so they should be your priority when entering combat. Heroes like Iron Man and Black Widow can work quickly with turrets and drones thanks to their powerful ranged attacks, but heroes like the Hulk might find it difficult to get close enough. Fortunately, each hero has a ranged attack to level the playing field.
Use Performance mode for higher frame rates
If you're playing on Xbox One X or PS4 Pro, you can sacrifice some of your extra resolution for a smoother experience. Marvel's Avengers runs at 4k / 30fps by default on these consoles, but there is a performance mode in settings that lowers the resolution to 1080p and unlocks the frame rate. It's not a locked 60fps, but it can be a bit smoother. Keeping it at 4k, however, can be a more stable experience, as the unlocked frame rates can be a bit wobbly. Check out Digital Foundry Analysis for more information.
Try out different heroes
Most people have a favorite Avenger, but you should probably try all six playable heroes at least once. Even if you settle for just one character as your main, there are several perks to using and leveling multiple heroes. You can't have duplicate heroes in multiplayer, so you won't be out of luck if you stick to one character and someone else takes them. There are also upcoming post-launch activities revolving across your entire squad, so you'll need to keep everyone level to get the most out of Marvel's Avengers. Each hero is fun to play, and you can customize each character to a surprising extent once you unlock more of their skills.
Pay attention to the types of damage
Certain pieces of gear will add additional damage types to your melee and ranged attacks. You'll see a bar fill up on top of enemy health bars when you launch attacks, and once that bar is full enemies will be afflicted with a status effect like Gamma Poison, for example. These effects range from Gamma to Cryo, and there are even a few surprising ones like Pym Particles, which reduce enemies after racking up enough damage. Pay attention to the gear descriptions to see if any of your attacks gain elemental bonuses.
Use intrinsic abilities
Every hero has an inherent ability, and these are essential to effectively playing these characters. Ms. Marvel's intrinsic ability, for example, is Polymorph, which allows her to dodge incoming attacks and deal increased damage. Using these abilities will drain your intrinsic meter, which is the colored bar under your health at the top of the screen. Some heroes like Black Widow work a little differently, but the intrinsic meter is still important to them too. Mastering intrinsic abilities such as Hulk's Rage, Iron Man's Energy, and Thor's Odinforce is key to success in Avengers.
Explore the loot
Some of Marvel's Avengers missions take place in open areas, and you should explore your surroundings for gear and other hidden surprises. By pressing the d-pad, you switch to tactical awareness which shows you nearby points of interest. These are marked with question mark icons and usually lead to chests, high value targets, or allies in need of help. More often than not, you will be moving away from these places with new equipment.
Some heroes can't open some doors
As you explore war zones and other open areas, you will come across various AIM gates that have loot behind them. You will have to solve puzzles or destroy objects to enter, but not all heroes can open all doors. Erasable doors can only be opened by strong attacks from heroes like Hulk or Kamala, while terminals can only be hacked by Iron Man or Black Widow. Companions AI won't do any of these things for you, so it may be worth playing around with online randomness just to have human players able to do these things for you when you can't.
Stun enemies for eliminations
When an enemy takes enough stun damage, they will become stunned and vulnerable to kills. To withdraw, press Triangle + Circle on PlayStation or Y + B on Xbox. Vulnerable enemies glow yellow. Kills deal big damage and are great for taking down tough enemies. Use heavy attacks and other moves with high stun damage to open up heavily armored enemies for withdrawal.
Start iconic missions early
Iconic Missions are optional mission chains that revolve around each of the six playable characters from Marvel's Avengers. They will become available whenever you unlock a new hero, and you should start with them as soon as you get them. Iconic missions have multiple stages, and a few stages require you to complete menial tasks like killing enemies or using abilities. Get a head start on these iconic mission chains so you can work on busy work steps in other missions.
Check your challenge cards
Marvel's Avengers has a battle pass system, but it works a little differently from other games. Each character has their own battle pass called a challenge card. Each challenge card has 40 levels and can only be upgraded by completing Daily and Weekly Challenges. When you unlock a character, take a look at their challenge card (it's the far right tab on the menu) and review Daily and Weekly Challenges to find out what to focus on. You can only level up the challenge cards through these challenges and you only get two per day, so it's best to start as soon as you can.
Don't invest too much in equipment early on
Equipment isn't important at the start of Marvel's Avengers. You'll want to make sure you're at the proper power level for missions, but gear should be considered replaceable and disposable until you're near the Avengers level cap. When you get equipment with higher horsepower, immediately replace whatever you have equipped. In this way, you will be able to quickly climb the ranks and level up your character higher and higher. Also, don't worry about the benefits or anything until much later. Just enjoy the campaign and worry about it all later in the Avengers Initiative.
Iron Man can share the Hulkbuster
Iron Man's ultimate ability is the Hulkbuster, but it's not exclusively for Stark. If you hold L1 + R1 on PlayStation or LB / RB on Xbox instead of just pressing it, you will be able to summon the Hulkbuster to a nearby area without entering it. Any member of the team will be able to walk up to the Hulkbuster and climb inside, allowing them to use your ultimate for you. This can be great for saving allies in a difficult situation or even just sharing your ultimate while you fly and focus on other targets.
