Enlisted

Other guide is pretty good, but wanted to post various methods I did that really got me good EXP rates to get consistent levels.

- I chose Allies on Normandy as out of the two campaigns (now 3 for non-series X) they had the most consistent win rates being the favored offensive team. Due to having 1000 lives and getting 100's refreshed any objective, (even more on the airstrip map due to destroying blips) even less skilled attackers compared to the defenders could consistently manage lucky breakthroughs to obtain the win and 1.5X multiplier. Playing on the defense, far too often do I see only one or two teams actually within the objective and really reveals why offensive stream rolls happen more than they should.

- Due to enemies being within a proximity on a specific point on the map, Allies have much more effective artillery barrages, mortar distances roughly calibrated, tank shots exploding in enclosed bunker sections or houses, grenades being guaranteed kills, etc.

- Prioritizing tanks and upgrading them was what really bumped me up in scoreboards, consistently getting 1/2 place. Finding a location with a little elevation and overlooking the objective, you can support the team while also ensuring the enemies are distracted and too far away to use explosive packs on you. I liked the Howitzer tank since it has bigger HE explosive radius. Bottlenecks like where the enemy would need to rush in to defend their point, or windows/bunker slits consistently give muti-kills.

- Always try to go for the various accolades which will also give a 10% bonus, up to a max of 5 for 50%. As I recall, there is one for being the best Squad type (Machine Gunner, Signal, Assault, Engineer, Best Tank Driver, Best Pilot, etc.) as well as being the top scoring in various ways to eliminate enemies ( Melee Kills, Grenade Kills, Most Tank Kills, etc). Lastly, there are two score based ones, being Top Score on Team, and All Purpose Warrior which is awarded for runner ups in score I think.

- In terms of specific ways for score, always have explosive packs on all squads and go for any tank you see, the 3-5 kills plus the tank kill is too good to pass up. Having an Engineer to deploy Rally Points will generate passive points from team spawns, and barbed wire will also give passive score from enemies going through it, especially good on defenses where the enemies will enter. On D-Day mainly, there are a surprising amount of MG42's that face into the Enemy Bunker Objective, or can be directed to where they come from.

- In terms of Squad composition, I think it is worth leveling the majority of them/going with whatever you want, I just made sure to always have either my riflemen or assault team, or both as they were the ones I performed the best at, as well as them being the soonest equipped and leveled. Getting the weapon upgrades from the myriad of support squads (bolt actions, carbines, machine guns, as well as ranking and equipping random engineers or gunners in other squads)
is more worth it than taking your entire roster of maxed squads everytime I think.

- Ranking up soldiers is based on personal preference, but I found way too late that it is probably best to level up them up to 4 or 5 before perks are chosen, as their skill pools will be the highest to get the upper tier ones, instead of ranking once at a time, and only getting access to low cost perks every time.
In my head at this time, one should consider is the strength-based perk that converts normally fatal damage to just incapacitating the solider, because the AI will still have the potential to get you more points. I also always tried to pick the Rifleman perk that reduces sway when readjusting based on some theory that it could help the AI land shots better, but I can't confirm. Otherwise, reload speed, run speed, crouch/crawl speed, more engineer material, quick medkit use, grenade throw distance, were other pretty useful ones.

All I can provide for now, but might update if I think of more things.

The requirements for this achievement changed after the campaign merge update in December 2023. To unlock this achievement, you must complete research 20 times. Research is found in the fourth tab of the main menu. It consists of a tree where you must work your way up to better earn weapons and equipment.

Research points are gained through general gameplay and are equivalent to the experience gained for your squads/soldiers. You must select a specific research to contribute points towards, and if you do not have any selected, you will accumulate points for later application. Once you complete a research, you must purchase it with the silver currency.

• The research does not all need to be for the same army/nation. You can complete 10 researches as the USA and 10 as the Germans to unlock the achievement.
• The research does not need to be in the same research line. You can combine rifles, tanks, machine guns, etc.
• If you made progress prior to the merge update, that progress has been reset, but the progress shown under the achievement did not reset. Don't be alarmed if you do not see progress updating.

I had gotten to level 18/20 in the Normandy campaign before the update, and my progress remained at 18/20 until I had completed research 19 times. I continued to do research as the USA. Once I saw my progress finally change from 19/20, I switched the the Soviets to complete a quick research and confirm that it counted as my final research for the achievement.

Not much to say really, just play a lot, kill a lot, capture objectives and above all: WIN THE MATCH (the score multiplier for winning is very helpful).
Don't worry too much about the xp grind though, you'll get this achievement way before the 100-hour one anyway.