*** Working method
Play now> challenges> Ace chemicals> pick challenge> exit game (when countdown begins works just fine)> play now> team deathmatch> sign out then sign back in and press a to continue.
This took about 95 seconds to earn a minimum of 10000-30000 XP depebding on rank in game the higher the rank the more gifted XP.
***apparently the below method has been patched I will leave it for reference.
There is an XP glitch for this game.
After completing a match in any game type it will show you the mvps after this you will get a loading screen and then it will place you into the lobby at this point simply goto the dashboard and return to the game to see your xp spike 10-20K
It has been said that it doesnt work properly until you hit level 53
***Read this for the remainder of the achievement as xp isn't everything!
The rest of the guide is just to help you with the other achievements
Now with that being said work toward your winning on every map for every playlist/gamemode. This can be frustrating as you will end up with 4 out of 5 and in my case I won on each map until finally it decided to give it to me so that can be buggy but eventually it will give it to you.
For the gadget achievement just equip the targeting goggles to your class you only need to kill 500 tagged enemies and tag 1000 enemies you should average near 50 tags a game and around 15 tagged kills if you are skilled at the game
my loadout is always nimble. I also run with the shield... The guns that I used where the gatekeeper with the partisan... Extended mags when you do empty out a clip switch guns to finish your kill rather than reloading. Know where the supply points are they will save you if you encounter someone while you are at a supply point move out and in to gain health to give you the advantage. If you take any damage retreat to grab some health
Now when you find the gun that suits you just go through the list completing the challenges for the different weapon attachments. ALWAYS aim for the head not only will you have to get 500 of these kills but it will almost always guarantee you getting more kills then deaths.
Your 50 Nemesis kills
these should come naturally as I got mine at level 60 I am now at 80 with 75 (I also MVP almost every game)
Focus on playing psych warfare as in this game mode you need to obtain 50 panic slap kills which also requires you to be losing... These will be hard as when the enemy team plants the battery and the counter goes down you get demoralized and will not have any ranged attacks only the melee panic slap. The enemy team always has you on radar making it a real pain in the --- to get close enough to slap the enemy go for the smaller characters as it is more challenging to multiple slap the heavier ones. I also have been pairing up with people inviting the ones with mics to a party telling them they can win if they let me have the panic slaps.
The 50 gold medals sounds intimidating but really its easy there is an excess of medals so you dont even need to do any of the challenging challenges. Just do all the easy ones for each map and then pick through the intermediate challenges that you want to complete to finish off this achievement.
Now just force your way through to that 200GS Good Luck