STAR WARS Battlefront

Legit way: As we all know, ranking up can be quite the pain in this game. Even if you are a beast in this game, it will still take you hours to get this achievement. I have found that the best game mode that offers the most XP in the time given is Fighter Squadron. In one of the most recent updates, you can pick up power ups that spawn an A.I. ship that gets kills for you. This is very effective as it can net you many, many kills and plenty of XP. Of course, you can play any other game mode if you are not a fan of fighter squadron, but it may take longer.

Also keep an eye out for the bounties that you can complete, which can be viewed in the main menu under stats or in the pause menu when in a game. These bounties/side missions give out to 1,500 XP all the way to 8,000 XP, which can really help in the long run.

Boosting way: There is quite an easy way to boost this that just requires yourself and three other players and the game mode Droid Run. To do this, you must find an empty server, such as the Asian or Brazilian Region and search for the game mode at the same time. When you have a group set up, split into groups of two and have you and your partner from the enemy team go to a droid and just stand next to it and hold . Doing this will give you vast amounts of points and XP. From my past experiences, I would end the match with about 50,000-62,000 XP.
[Edit] I would also like to add that you will have an easier time doing the boosting if everybody has the Outer Rim DLC and you do the droid run on those maps. I say this because that DLC is basically dead, which means less randoms and annoyance.

They will also most likely have a XP event in the near future to celebrate their new DLC, as they have done in the past, so that would be a perfect time to get this done if you haven't yet reached this.

I hoped I helped out and gave you guys some solid advice.
If you guys found this useful, feel free to up-vote and happy hunting!

You need 5,975,100 total EXP to reach level 100. You can check your EXP total by hitting on your gamer picture at the top left of the main menu and checking your score stat (since score = EXP.)

Beyond playing legit, which is a foregone conclusion if you're looking up a solution for this achievement, there are two methods to boost this effectively. Both of them require changing your region to Asia by opening Settings, then EA Account.

The first method is the most popular: droid run. Using 4 or 6 people, everyone pairs up with someone on the opposing side at an objective. Simply follow the gonk droid around and hold . You get about 6,250 EXP per minute this way but you cannot stand still for longer than about 3 seconds before the droid walks out of capturing range, so it's a very involved method. Droid run matches also must absolutely end after 10 minutes so you will be doing a lot of loading between matches.

The second way is drop zone. You can only use 4 people for this mode but the method is the same; find an objective and hold . The benefit of drop zone is that the objectives do not move so you can just set something heavy on your button and watch Netflix, but the drawback is that you earn 4,550 EXP per minute. Fortunately, matches do not end in drop zone as long as the score is tied so you can avoid a lot of loading time.

When in drop zone, you will begin with a single capture zone. Ideally you want to switch around the people who get this first pod in the interest of fairness. After 3 minutes, a second drop pod will land. Now everyone can boost at the same time.

The only gotchas about drop zone:
1) wireless controllers are a hazard because they will shut off despite having a button held down, since it probably assumes this constant input is accidental (e.g. having dropped your controller upside down on the floor.) If your controller is wireless, keep it within reach and either taunt or check the scoreboard once in a while. Neither interrupts your button.
2) the servers do not seem to be designed to stay continuously functioning for longer than about 30 minutes, so at some point the match is simply going to crash out and all the work you did will be lost. Ergo, you want to let one team take both pods when everyone's gotten 150k EXP or so. Going beyond 200k is dangerous, and you'll never reach 250k before the servers go out.

One thing that is often over looked but can make this significantly easier is to go for the challenges. When you start any game, you should have 3 challenges displayed on the right side of the screen. You can select a new challenge for 100 credits.

What I did was kept switching for new challenges until I had: 75 Kills, 50 Kills, and 50 Kills w/ a Vehicle. By the time I completed all three (about 3-4 games), the rewards from the challenges came out to about 22,000 XP. No need to select those specifically but just tailor them to be something that suits your play style (Blaster Pistol Kills, Rifle Kills, Droid Captures, etc...)

Once you finish all three, simply back out of the next game and then join a new one and the challenges will be at 0%., ready to rinse and repeat. It will still take a solid chunk of time but you basically get the equivalent of two well played games every time you complete all three challenges.