One shot Pathfinder level 1 game

[fulong]

Recommend me a crazy high DPR legal level 1 build for pathfinder. No 3rd party or rich parent traits.

[Keldar]

Its 1st level, just have a high strength and a big weapon and everything will die swiftly.  Fighter, Barbarian, or anything else proficient in Greatsword or similar.  2d6+Strx1.5 is great against things with less than 16 hps, which is most of what you'll be facing.

[Jackinthegreen]

Keldar's pretty well got it nailed.  1st level goes to smashing stuff with a big weapon and the greatsword is, well, great for that.  It's better than the greataxe since it does more reliable damage too by virtue of two dice instead of one for damage (meaning that a 7 is one of the most likely numbers to come up in this case) and its larger crit range.  The greataxe's crit multiplier will tend to overkill stuff when it does manage to crit.

Barbarian or paladin would be my picks.  A ranger could work too.  Fighters don't have great feat options but it would still be serviceable.

[sambojin]

High strength rogue. Slap in a bit of Dex and heaps of tumbling and bluff.

It's not that different from anything else, other than an extra +d6 on weapons from time to time. Human it for a weapon.

(not sure on PF, but if it's anything like a 3.5 lvl 1 only campaign, high strength human rogue, with dexterity and charisma secondary. Bluff, tumbling, whatever else. Feat a big weapon(2d6), feat something else with it. Big damage + d6, plus another feat worth of stuff. 3d6+1.5*Strength bonus, plus other stuff, kills most stuff, even if you have to be tricky with it.).

[Frogman55]

Str 18, Dex 14, Con 14, Int 10, Wis 10, Cha 10 (Assuming 20 point buy. You could dump Int, Wis and Cha farther and get your STR up to 20, but that will only give 1 more damage per hit - this probably isn't worth the -1 will and lost skill point. If you do want to dump, you could dump Int and Cha and boost your Con, which may be worthwhile).

Human Barbarian

Feats: Power Attack, Combat Reflexes

Favored class: If you're never going to get to level 2, get an extra HP. If you are going to level up, use the human FCB to the Superstition rage power.

Weapon: Guisarme (Or Ranseur, I usually prefer the trip ability). Grab a spiked gauntlet (or armor spikes if your GM is picky)(You can also use a Lucern hammer, which has a higher average damage output, but is more variable and does less with a crit).

You'll be doing a base 2d4+6 damage a hit. (+9 if you rage or use power attack, +12 if you rage and use power attack). That's an average 11(or 14 or 17) damage per hit. The reach weapon and combat reflexes should give you more than one attack per round (up to 3 AoOs). Spiked gauntlet means you threaten adjacent stuff, in case you aren't able to 5' step.

Get the best armor you can afford - Guisarme and spiked gauntlets cost 14 gp (59 if you have to go with armor spikes). Either way, your best bet at first level is probably scale mail- 50 gp for +5 AC and a -4 ACP. That'll give you 17 AC (15 if you rage), so you may still get hit a lot. But that'll usually be from archers, as something more than 10' away will usually provoke an AoO from you, giving you a good chance to lay them out.