Hollow Stumps sit in the mid band of a run, so you will reach them once you are past the opening stretch but with plenty still ahead. They are containers you pick up on the Operation: Egg Heist map, where eight are marked in total. Six of those cluster at the Ancient Altar, which makes it the natural place to start and the bulk of the work. The remaining two lie further off at the Mountain Sanctum, so plan the Altar first and treat it as the anchor for the sweep.
Areas with Hollow Stump
| Area | Level | On the map |
|---|---|---|
| Ancient Altar | — | 6 |
| Mountain Sanctum | — | 2 |
That leaves the two at the Mountain Sanctum, and the question is whether they justify the trek out. On balance they do, but only after the Altar is cleared. Since you are already committed to the six-strong cluster, finish that in full before making the walk across, so you make the journey once rather than doubling back. Handle the Sanctum pair as the tail end of the sweep, and you will have all eight without wasting a second trip.
Open the Aniimo interactive map to see it with every other filter, or pick another from the list.