To start Operation Scarlet Spear in Warframe, you will need to head to the Scarlet Spear Flotilla. You can find it orbiting Earth in your Navigator, close to the Strata Relay.
Load in, and you will arrive at the main Operation room. You can find Little Duck on the right side. Speak with her, and she will give you the introduction to the Operation. When she is finished talking, you can purchase an OpLink from her for 1000 Credits.
When you purchase the OpLink, be sure to place it in your Gear Wheel before you start any missions. You can find an Arsenal station on the left side of the room.
Now, it’s time to start your first mission. In the center of the room, you will see a running count of active squads for the Operations two mission types, Ground Assault and Murex Raid.
Ground Assault involves taking on the massive Sentient Condrix, and the Murex Raid involves going after the Murex ship itself.
Pick whichever one you wish to play, and you will be loaded into the mission. The missions have matchmaking for people who do not have a full squad. The Murex Raid is in the yellow area on the left side of the room, and Ground Assault is in the blue area on the right side of the room.
How to Use the OpLink
To use the OpLink, you will need to equip it in your Gear Wheel, then use it during the Ground Assault mission when the Condrix has been defeated. Put down the OpLink to scan the Condrix, and send a Kill Code to a team playing in the Murex Raid.