There are 6 groups nearby — 2 groups immediately outside the portal, 2 more at the north end of the jelly-bean-shaped rock, and 2 more on the west side of the arrow-shaped rock.
Each group consists of either 3 Sand Giants or 2 Sand Giants and 1 pop-up Rockshot Devourer for a total of 12–18 giants per run.
One group in each pair will start walking as soon as they enter your radar, the other group a little later. If a group contains a devourer, the giants will stop about an aggro bubble away from their spawn point, since the devourer can't follow.
Threats & recommended skills
Threats: general threats like hex, condition, environmental effects etc.
Tactics: important tactics, for example pulling, choke points etc
Recommended skills: skills like anti-kd, hex removal etc