Originally Posted by
Plutocracy
Good splits for these are:
1) 13rog/6monk/1fighter- 11 feats, improved evasion+crippling strike, 8d6+12 sneak attack (+2d6 if assassin), +1 monk AC, Tier II monk stances, monk speed II, fastest sneaking in game (+60%), rogue hasteboost IV, 10% healing amp
Could go assassin II PrE with rogue here for extra 2d6 sneak attack, or thief-acrobat II for slip/trip immunity and quarterstaff speed/dex bonus to sneak attack, and super super movement speed.
2) 12monk/7rogue/1fighter - 11 feats+free improved crit: piercing, improved evasion, 7d6+9 sneak attack(+1d6 if assassin), +2 monk AC, Tier III monk stances, touch of death, immunity to poison, monk speed IV, Rogue hasteboost III, 30% healing amp
Pure rogues get 14d6+12 sneak attack (up to 17d6+12 with assassin), so if you want to do best DPS pure rogue is best. BUT, monk gives huge bonus to saving throws, AC, movement, immunities, healing amp, feats, and ki strikes.
Best DPS will be pure rogue, but a sturdier faster build will be one of these ninja spy builds. If you want to be a quarterstaff user, go with option 1) and take thief acrobat. If you want to be a shortsword user, option 1) or 2) are both good.