I know this has been discussed but here is a little more info in this article:The Deleted Predator Weapon That (Accidentally) Still Appears In The Movie
In the original Van Damme design, the hunter's main weapon was a gun that fired razor-sharp spears. While this weapon isn't seen in the final movie, it's still used to take down one of the squad.
Jesse Ventura's Blain is the second member of Dutch's (Arnold Schwarzenegger) team to die in Predator. Viewers may recall during his demise the character is shot by something offscreen in his shoulder, with the dazed soldier then being shot in the back by the Plasmacaster. Pausing just before the impact of the shoulder wound, it's possible to see that he's hit by a spear-like weapon, which was intended to have been fired by the Van Damme version of the creature.https://screenrant.com/predator-movie-deleted-weapon-appearance/