Teams of 3 are easay. All you need is a couple of arrows, a decent sword/axe/pickaxe/shovel, flint & steel and a fishing rod.
I managed a 5v1 in SG3 with all having better items than me.
I had 3 burning tools, a stone sword and 4 arrows, with 1 1/2 fishing rods. I ran into corn and 3 guys ambushed me but missed. 2 more players decided to kill me, and I realized I was screwed. Using the darkness of SG3 and them huddling together, I "juked" them and they hit each other, then I burnt the floor, and 4 were running to the water. Leaving one man behind, I finished him off with a few blows of my sword. Upgrading only my chest plate and eating a golden apple, another guy started chasing me. I set the ground on fire, and he caught on fire. I hit him several times and he ran back to his friends who were 10 blocks away. I managed to burn the 3, run away as they had weakened speed, and sniped the guy twice, to death. And then, my friend sponsored me a poison potion. I splashed it at their faces, set them all on fire, with the darkness and effects of burning and poison, I killed 2 of them with 3 hearts to spare. Eventually, the last guy made a mistake - eating a golden apple at close range. That gave me 3 options - Get hits, put on armor or eat my golden apple. I ate my golden apple and upgraded 3 bars of armor. I used the last of my burning tools, and I got him low. He started running, and I fired at him with my remaining 2 precious arrows. And, I ironically won the game.
Was special as it was my 250th win c:
(I'm not being a show off fag)