cpm3a strategy guide
From PromodeWiki
This is probably by far the most popular duel map for CPMA and it's literaly been used and abused. Map features 4 powerups: RA, 2x YA and MH. The most common choice is to control RA, get some YAs between and occasionally MH, when you're in need of health.
However, when you become more advanced it's good idea to control all these 4 items, leaving your opponent with shards or nothing at all. This might be hard if you want to time these items, but instead try remembering the order of three armors, get into fights with enemy in between (so you lose some armor and are able to take another one without self damaging yourself) and go for MH soon after it expires (20s after wear off → Tech Sheet).
If you aren't able to hold whole map tight, you could handle with only RA as it gives most power, as long as you keep your opponent out of other powerups.
When you're in control, after every frag you get, shoot nearby spawn points as most probably there is one close and there's always small chance to get another easy frag. If you don't see enemy spawning nearby, you might want to shoot at further points of map, where he might be. For example, if you just killed him at RA, spam PG at exit of teleporter. This way you shoot at exit of MH tele as well and he might catch some hits, or get totally smashed on attempt of swooping RA from you when he spawns at the other end of tele at RA and goes through tele to you.
When you're on the down side, you shouldn't rush for anything - that's what your enemy expects, you can be easily killed when running for armor as that's the most obvious thing you can make, and he should know that too. Instead, try waiting in silence for him to go in other part of map while you wait for one of the powerups spawn. As soon as you get that, you should surprise him and take over. Teleporter at RA comes in handy, camping on the other side of it (at shards / LG ammo) might get you easy hit at his legs and then shoot a rail or shaft in his face.
As this is very old map, you need to surprise opponent in order to take over it. Rocket jumps, neat grenades in opponent's face or camping at one of the teles exits can be useful, however don't abuse that as everyone learns quickly and won't do the same mistake second time.