it's three trials one is to knock off ten components off a grazer (a deer) well at first I tried this with arrows and didn't do to well. Later I bought a new bow that came with this arrow that does no damage but instead blows off all componenets on a robot, so using that I easily got gold rank.
The came use log traps to kill robots, wait what log traps?! Omg there are ewok style log traps ready to be shot down on the sides of the cliffs. So I throw a bomb behind the pack of grazers, they start running into the path with all the log traps and I shoot them open and watch logs take them out. Awesome.
The hardest one was using a blast trip wire to kill six robots in under three minutes. This takes prep time so I lined up the paths with some wires , threw a bomb to try to lure them but they went a different way. One time they hit one wire and they all turned around so they didn't run into my other wire. I didn't get gold the first time. The second time I lined up the three paths with wires and decided to lure them down one path, then back down another and that way they go back and forth and hit the wires. Got it, got all golds which gave me a skill point and loads of exp. just messing around and killing so many robots with the trial exp leveled me up like three times.