The Godslayer is a collapsible sword that was used by Gamora which includes a detachable knife that connects to the sword's hilt.
When Gamora pursued Peter Quill on Xandar, she was interrupted by Rocket Raccoon and Groot, and used the Godslayer to defend herself from the pair, amputating Groot's arms when he attempted to restrain her. While imprisoned in the Kyln, the blade was confiscated by the Nova Corps, but Gamora eventually reclaimed it after escaping from the prison with Quill, Rocket, Groot, and Drax the Destroyer.
The Godslayer was presumably destroyed on Knowhere by Thanos, who effortlessly broke the blade before kidnapping Gamora. However, this turned out to be an illusion created by the Reality Stone. The weapon was then collected by Quill.
The Godslayer is capable of cutting through even the most durable of metals and uses a unique energy core located in the hilt to lower the weight of the blade, making it easier for the wielder to handle. The detachable knife can be used as a melee or throwing weapon. It can also be split into two swords, although this has not been demonstrated yet.