Basically 4-6man dungeons where 4man is the most difficult one. There's also a solo dungeon called mushin tower where you climb floors and it gets progressively harder to the point where you must completely master your class to beat the 8th floor (more floors gets released after 50cap mini-expansion).
If EU/NA follows Taiwans release schedule it's going to be one dungeon release every month to catch up to the Korean version.
There's also a few "24man" questing hubs with world bosses for everyone in that channel, up to 24 people. It's okay for new players but I would honestly compare it to a slightly harder LFR in WoW.
And way down the line we will get the raids that they are just now introducing to Korea, 24man raids with complicated mechanics.
1v1/3v3 arena with equalized stats aka gear has no impact, no potion usage or anything brought from outside the arena.
Faction area with a few world bosses, knowing the west there will be no peace treaties
At 50cap (4months after release more or less) there will be a guild vs guild island event that opens during the weekends. You must first do some openworld pvp/pve to gather prestige points to enter with the help of Blade & Soul Power leveling, and once you enter it's basically a capture the base type of battle ground where you need a base in order to respawn if you die (3 bases in total). So to "win" you must take all bases and defeat the remaining opposite guilds (can be more than two guilds at a time). Your reward is the ability to farm a few loot piñatas with strict dps requirements.