I decided to pop double dragon into the super game boy while I was drinking to relive one of my favorite childhood games and was surprised when I cleared the game from start to finish without losing a single life. I have included some links below for those who want to skip to certain stages.
Mission 1 -- 0:38
Mission 2 -- 3:38
Mission 3 -- 6:23
Mission 4 -- 12:17
While most of the strategy is apparent in the video, I wanted to outline a couple key parts where I have discovered certain tricks or a certain technique to get through difficult portions of the game.
Abobos are very challenging in this game for their endurance and crazy reach. I found the best thing to do is to walk up and down on the screen edging your way closer during each pass so you can get inside their long distance arm reach.
At some points in the game you can actually freeze Abobo at the edge of the screen, as seen at the end of Mission Three. At points in the game where there is uneven terrain at the bottom of the screen you can position yourself on the lower portion of the land. Abobo will creep up to you but stay firmly planted on the upper ledge, however if you slowly creep up to his level you can elbow him without him being able to retaliate. This helps for easy kills in Mission 3, as you get to the cliff section and also for Mission 4, after you defeat the enemies and the skull doors conclude trying to suck you into spikes.
At the end of the Cave in Mission 3 you must face an Abobo on level ground without any maneuvering room. This is the portion where the ground starts to vanish after crossing some lava pits and fighting two Ropers. At this point it is hard to attack him without getting beat up in the process. One thing to note is that Abobo will take out a lot more HP if he manages to grab you verses if he hits you once in the air. What I usually count on is surviving long enough for Abobo to back track into the expanding pit. In order to weather his attacks you must be on the right hand side of the screen, otherwise he will simply knock you into the pit. I execute a drop kick to temporary stun him and then immediately jump kick again away from him. At this point he will probably hit you with one of his hay makers, but you will be rooted on the right side of the screen. Now the trick is to constantly jump kick when you character gets back up. You want Abobo to continuously knock you down with one hit rather than grabbing you. Every time he knocks you down he will either stand in the same position or wander backwards before he starts another attack. Once the ground has decayed enough, he will fall to his death allowing you edge your way to the door which will be close to the growing pit at this point.
Another cool thing is when enemies can be lured to falling off ledges. This can be seen near the end of Mission 2 where a pair of Lindas and Williams will come out of a door. If you position yourself on the lower third portion of the platform and start attacking one of the enemies, the other will shuffle downward waiting for you to finish and fall off of the platform. I demonstrate with the Lindas but you can also coax the other pair into following suite.