nodus
just kidding of course, nodus, bsm or any other hacks/mods are not the answer
there are a few strategies I use to take out teams. note that its preferable to take out teams BEFORE deathmatch, that way if you cant handle the team you can team with others to take them out, or run away to catch them in a trap, or more preferable are (for example, on breeze island, I force teams into the water if I know they don't have arrows and then shoot them to death.
1: traps. catching people in the gravel trap on sg4 gets you a lot of hate, but it feels good, and just think that you don't have to deal with at least 1 member of the team. another one is the lava parkour on sg4, where you can easily just hit someone into the lava.
2.cherrypicking. while it pains me to resort to this, sometimes its the only way to survive. catch the team off guard after they fight someone else, then go in for the kill. it works too. ill never forget the time when I killed a team of 2 in full iron and iron swords on sg2 when all I had was full leather and a stone sword because one teammate made the mistake of saying "regen I have 1 heart"
3.flint and steel. one of the best tactics in PvP in general. its harder to see and hit people while on fire (unless you have a texture pack like mine where the fire doesn't get in the way really) and it opens opponents up to get murdered by arrows. catching both on fire usually allows you to at least break up the team even if you die, even if they have better gear
4. fishing rod. honestly, I cant do this tactic for abything, but it works for other people well. fishing rods stun people so you can land hits easily. using this tactic against a team can usually allow you to severely weaken one member before they have to separate.
5.just turn around and shoot them in the face repeatedly before taking them on. most teams I find I have more skill than, and I can easily kill them off
hope these helped