Double Dragon 4 (EP)

You can cut your runs in half by using a second controller. Make sure your main account is assigned to both controllers. Pick the 2 character achievements you're after, and let player 2 get a game over right at the start.

You can do this in 2P-B mode and kill them yourself, or move both to the second screen and walk left off the raft 3x. Finish the Story, and the player 1 achievement will unlock right away. In 5-6 minutes, the player 2 achievement will unlock.

It is vital that you configure custom controls, so jumping and activating specials can be done with 1 button input. Default controls are finicky to accomplish either. Recommend: Punch = X, Jump = A, Specials wherever you want, I used LB, RB, and Y. Kicking was B, but I never used it.

When I beat the game with my last character, it was about 5-6 minutes later, the "many characters" unlocked, and then about another 5-6 minutes after that got the "all achievements". I was just playing tower at this point to see if they'd pop, and they did.

To unlock every character, I think you basically just need to finish the game once, which unlocks Tower Mode, and then progress there to Floor 45-50. Of my early unlocks, I used Abobo in tower to do this.

If you game over your first run as Billy or Jimmy, you can press Start on the main menu to cycle through completed levels to continue where you hit game over. All character achievements must be done from Mission 1 through 12, without game over.

If you game over, you cannot use stage select and get those achievements. This is useful to know though, as you can unlock Tower Mode, and the general story achievements.

NOTE: While you cut your runs in half doing this, be aware that you will be fighting more enemies due to 2-player mode, but you get 2 extra credits to finish with.