Renegade Ops
15 Achievements
8-10h
The Daily Grind
Get a character to max level
4.7%
How to unlock the The Daily Grind achievement in Renegade Ops - Definitive Guide
Level 2 is great for gaining tons of experience, the key is linking up those chains between clumps of enemies. Its easier to practice during the 'Destroy the Mortars' section of level 2 since those enemies are all quite close and your bound to gain tons of experience trying.
Also note - this achievement MUST be gained while in SINGLE PLAYER.
If you max out a character while online, the achievement won't unlock which would suck if you were on your last character!
This will probably take you a little more than one playthrough to earn the maximum level if playing through on Normal difficulty, but all you have to do is continue playing. Even if you fail a level, you get to keep your earned experience so your best bet is to just keep at it.
WARNING: As the trophy specifies, this must be done in single player. If you hit level 45 online or in local co-op, you will have to delete the save file or start another character for this trophy.
Not possible while playing on Easy. You will only gain experience points, and rank, by playing missions on Medium/Hard difficulties. You will likely get this just from doing all the missions on Hard and completing secondary objectives on Medium/Hard. If you managed to do all that and still aren't at level 45, just grind out some more points by replaying missions.
This trophy will pop when you get to level 45. (While you can increase the bar to maximum again after that, you won't progress to level 46.) You will now have just enough points to unlock any remaining upgrades. (If you purchase upgrades when playing online, you may lose those points and not be able to choose all the upgrades. This bug does not affect any trophies.)