Either Xbox live is being weird or a new gambit game mode is coming
Its a strange thing that has been happening lately that when people play certain activities it displays a game mode and type however the only time i have seen this gamemode was in the crucible labs.
The Game Mode is Lockdown
This in my opinion would be an interesting addition to gambit if it is the same game mode that we once played in the labs, now this could be one of two things, microsoft fudging the muffin or
Gambit could be getting an interesting new mode with larger maps that focuses around map control, ot could end up being something akin to a moba where its 6v6 on a large gambit map (and im talking large that you need to use your sparrow to get around) each team has their own minions and primevil, the goal it to defeat the other teams primevil. In essence you have the enemy team on " Lockdown"
Im sorry for those of you who hate mobas ( i also don't exactly have a soft spot for them ) however a game mode like that would actually be really good for gambit as it fits the mold of a moba quite easily
their can also be stylised armor sets based around this as well.
Personally im not a fan of those kind of games, but with destiny you could put a really unique spin on it.