Nothing new to grind both prerequisites — Completionist Cape and Master Max Cape — are already tracked on their own tabs; once each reads 100%, this one is automatically satisfied too.
Not purchased — admired wear the master max cape, keep the completionist cape in your inventory (worn at least once), then admire the Ornate Grave in Falador Park and pick the Completionist cape option.
Questions
How many requirements does the Master Completionist Cape have?
29 skill requirements, on top of the Completionist Cape and Master Max Cape.
What is the highest skill level the Master Completionist Cape needs?
Level 120, in every one of its 29 skill requirements.
Do I need another cape before the Master Completionist Cape?
Yes: the Completionist Cape and Master Max Cape first.
Track your Master Completionist Cape progress
Sync your RuneScape name and check off every requirement above. Free, no account needed.