The Nine have decided to throw a bunch of Exotics on Guardians again and sent Xur to deliver them. Titans drew the short straw this week.
Xur is located in the Watcher's Grave on Nessus. To get to him, spawn on the aforementioned location and head towards the golden barge. Enter its cargo hold from the rock formation below and proceed up the ramps until you reach a pile of chests and the tentacle guy among them.
Merciless is the weapon of the week. While Fusion Rifles aren't exactly popular right now, this one can be useful in taking out beefier enemies since its charge time gets lowered whenever it doesn't score a kill. When it does, however, reload for a fancy version of Kill Clip. Overall, it's a good Exotic for beefier PvE enemies but not the best in PvP.
Titans got Aeon Safe gloves this week. If you don't have them in Collections, buy them so the Fated Engram doesn't blurt them out instead. After that, it might be best to shard them so they don't take up vault space.
Hunters are getting Foetracer this week, which can be useful in PvP for the wallhack it provides and in PvE for the bonus damage on low HP targets. The bonus damage is around in PvP too but the threshold is so low that you will almost always kill the enemy before the buff kicks in.
Dawnblade Warlocks got the best Exotic this week as it allows them to float and aim their weapons which will improve their accuracy, flinch resistance and damage resistance. It's great for top tree Dawnblades in PvP. Grab a pulse rifle and just score cheap kills all around.