"Beast of Reincarnation" has a large number of special achievements, many of which are quite troublesome to complete. Ultimate Vessel is one of them. The achievement requirement is for Emma to reach level 100. For mid-game leveling, it's recommended to use the bonfire at Pilgrim District - Clock Tower Inner Hall. You can stay stationary and shoot with a bow, remember to equip auto-tracking.
How to Complete the Ultimate Vessel Achievement in Beast of Reincarnation
Ultimate Vessel
Emma reaches level 100.
For mid-game, it's recommended to use the bonfire at Pilgrim District - Clock Tower Inner Hall for leveling. You can stay stationary and shoot with a bow, remember to equip auto-tracking.
Sit at the bonfire right after killing them
For late-game, it's recommended to go to Royal Capital District, Mount Hiei Area, Overlord's Nest Entrance.
The spot where normal players get stuck in the second playthrough is more suitable for farming skill points.
I started leveling up only after finishing the second playthrough at level 72. The Withered Beast in the Meteor Crater can be taken down with half a skill combo, giving 1300 XP + 20 skill points every 40 seconds (actual combat takes only 5-6 seconds, most time is spent traveling). I reached level 100 in just 25 minutes.
However, even after reaching level 100, I still didn't have enough skill points. In this game, skill points depend entirely on the number of small mobs killed. Killing 1 small mob gives 1 skill point. Stronger enemies give more skill points, having nothing to do with XP gained from leveling. The most annoying part is that the stat reset function doesn't reset C-skills, causing me to miscalculate two or three times thinking I had enough points to max out skills. When I started save-scumming to reset stats, I frantically clicked for ages only to find I still didn't have enough points, wasting all my effort.