Heirlooms are the rarest cosmetic items in Apex Legends, and the only Heirloom set currently available in the game is for the Wraith.
One of the items in that set is a melee weapon skin, which is a metal knife that's shaped similarly to an arrowhead, but emits blue energy.
Fans of both Apex Legends and Call of Duty have noticed that the melee weapon looks very much like the one used in the 'Cliffhanger' mission from Modern Warfare 2.
In that mission, the player is able to hold their knife and pistol simultaneously, setting up for a pretty awesome look.
With this in mind, Reddit user 'Deraged1337' proposed that Respawn made an adjustment in-game that would allow the Wraith to hold their Heirloom melee and weapon the same way, assuming they're using a pistol-type weapon like the Wingman.
While this may not really end up having any effect on gameplay, it would give players another option with which to use their Heirloom, since there aren't too many ways it can be used currently in the game.
The post currently sits at over 14,300 upvotes on Reddit, so it's safe to say that most players would probably like having the freedom to use their Heirloom melee this way.
There are currently only three Heirlooms in Apex Legends, and they come as a single set that's solely available for the Wraith. The set includes the melee weapon skin, a Banner Pose, and a Intro Quip.
These items can only be unlocked by opening Apex Crates, but they are so rare that the chances of getting them are less than 1%.
However, in order to make all of them at least reasonably possible to get, any Crate that's set to contain an Heirloom will automatically award the player with all three.