ancestor
announcer
antecedent
avant-garde
bellwether
buccinator
bushwhacker
explorer
forebear
foregoer
forerunner
front runner
frontiersman
fugleman
guide
harbinger
herald
innovator
lead runner
leader
messenger
pathfinder
pioneer
point
precedent
precursor
predecessor
scout
stormy petrel
trailblazer
trailbreaker
vanguard
vaunt-courier
voortrekker
conceiver
mastermind
originator