Heavy Barrel (Cybertron)
Trigger is a Mini-Con from the Cybertron portion of the Unicron Trilogy.
Trigger is one of the many Mini-Cons hailing from the planet Cybertron caught up in the events caused by the Unicron Singularity.
(Note: Many fans place Trigger as the Mini-con partner of the Decepticon Buzzsaw, as Trigger's mold is the partner to the original mold used to make Cyclonus. However, the packaging for the assortment Trigger was available in does not give any of the Mini-Cons a faction affiliation, so there is nothing to officialty say who these Mini-Cons work with, if anyone.)
Toys
Cybertron
Trigger is a redeco of the Mini-Con Crumplezone, transforming into a Cybertronic tank. He can also form a cockpit with underslung cannon for the Armada Cyclonus mold, though the remolding on Cybertron Buzzsaw makes using him with that version difficult. Available only as part of the fourth Micron Booster assortment in Japan, Trigger came in a "blind-packed" box that prevented the buyer from knowing the contents of the box until it was opened.
