Harvester

Harvester is the gun that started the ancient gun line. It was the 30th and last tier of the Halloween Event 2021 Main Event, priced at 80,000 Candies, and the wiki's trivia says the full climb to that tier cost 97,400 Candies in total. The same page notes it cost the same amount of Candies as the Elderwood Scythe. The event is long over, so trading is the only route. IDontHaveAUse designed it.

Crossbow firsts

It is the first ancient gun and the first crossbow-shaped gun, with Icepiercer following as the second of each. The model is a crossbow of dark stone and steel that fires an emerald-green arrow along a matching green line, which is unique to it. It also has its own shooting sound, a feature the wiki says only a few guns share.

The Candleflame Glitch

Harvester was a targeted victim of the Candleflame Glitch of 2021. The wiki says that led Nikilis to ban people who held large amounts of it, which makes it a case where owning too many copies carried a real risk.

Leaderboard versions

Blue, bronze, silver and gold Harvesters were awarded to the 2021 Halloween leaderboard as unique trophies. The two Candy figures on the wiki describe different things: 80,000 is the last tier alone, and 97,400 is the whole climb.