Capture the Flag
Capture the flag is one of those game types where each player is very interchangeable. By this I mean that the players role changes depending on the situation. I'll give examples of this later.
Also, remember that sometimes "Slayers" can be called "ARs (Assault Rifles)" and "Objectives" and "supports" can be called "SMGs". Another thing to bare in mind is that sometimes a support can use an assault rifle and be called and "Aggressive AR".
Slayer:
Like in Hardpoint, the slayer needs to be a person with raw gunskill. Knowledge of spawns and spawntrapping is also extremely useful, if not a necessity. The slayers role is to gain map control by killing enemies and advancing into the centre or edges of the map. Map control is one of the most useful things in CTF. By having control over large areas of the map, the opposition is forced to attack and open themselves up to gun fire. You however would be behind cover and would rotate between headglitches for that element of surprise. This allows the whole team to run toward the enemy flag without having trouble from the enemy. Also, when your team pulls a flag, the flag carrier has constant support and can run most of the way without difficulty. Earlier, I mentioned that the rules are interchangeable. An example here would be that if 3 or 4 of the enemy team die, the perfect time to pull, and the slayer is the nearest to the flag, he should pull, even though it is not his job. The rest of the team should then fill in and act as slayers and supports.
OBJ:
The objective player is the primary man for pulling flags. The would almost always use an SMG. The OBJ will need to be able to make quick decisions on where to pull and whether or not to Pre-aim. For example, if 4 members of the enemy team die or a team mate is just round the corner , pre-aiming is not necessary. However if you are pulling into unknown territory, pre-aiming needs to be balanced with sprinting. This will take much experience. The objective and the support will swap jobs at a moments notice, so ready yourself for your team mates command.
Support:
The support player has many jobs. What needs to be done depends on the teams positioning and the current situation. Primarily, the OBJ needs to be either followed or lead by the support. This is to kill off enemies or pick up the flag of it is dropped. If the flag is already guarded, the support can go to cut offs. Cut offs are positions where the enemy had to pass through to reach your flag carrier. By guarding these cut offs, the enemy can't reach or, therefore, stop your OBJ from capturing the flag.
Stale Mate
Stale mate is the term used to describe when both teams have each others flag and are waiting for the other to be dropped and returned, so they can capture the oppositions.
Hardpoint
In Hardpoint, there are 3 main roles; Anchor, Slayer and Objectives .
Anchor:
The anchor is possibly the hardest role to understand to a newcomer. The anchor literally anchors the team to a spawn. In other words, by sitting in a certain spot or area, they maintain the spawn area for their team. This can give significant advantage to the other members of the team, as hills (hardpoints) are sometimes easier to defend from a particular side. Also, the anchor can scout enemies to their team mates, as well as pick a few off at long range. At around 20 seconds left in the Hardpoint, the anchor should rotate around to gain the spawn of the next Hardpoint, leaving his team to defend the previous one. Keep in mind that there is always players attempting to kill the anchor so the Hardpoint is easier to break for them.
Slayer:
The slayer does what it says on the tin: slays. This player needs to be extremely good at killing multiple enemies and staying alive without nessicerily being behind cover. Sometimes, if their team has control of the hill, the slayer may push out through the hill to stop the enemy before they reach the hill. Advantages of this are that the gun fights aren't happening in the hill, meaning that contesting doesn't occur and they can tell their team members where the enemy is. Also the slayer had a bonus advantage over the opposition. This is that opposition are sprinting towards him and the Hardpoint, instead of pre-aiming. This means the slayer can get first bullets off and should get the kill. When the opposition has the Hardpoint, the slayer will also help break it.
Objective:
The are usually 2 objective players, although 1 of them may, at points push through like the slayer to slow the enemy down. The main role of the objective is to break and hold hardpoints. Sounds easy? Not when grenades, concussions, smoke and 3 enemies come hurtling towards you. These players so have the advantage of cover when defending the hill, but also have to have a good aim and gun fight strategy to capture it. The most effective way of breaking the hill is team work. It sounds over rated, but it really isn't. If one of the 2 OBJs throws a smoke and the other runs in, shortly followed by his team mate, 3 enemies are a lot easier, especially with the help of grenades and the slayer. The objectives also need to have good reactions and prediction, as they need to react to enemies in an unexpected corner and to predict where the enemy is coming from.