Dynamic list of values based on dataset

[mattadler22]

I am trying to create a dynamic list of unique values, based on the value of a single cell that can be found in the dataset being used.

My dataset is 2 columns:

Pool Manager
1 John
1 John
1 John
1 Mike
1 Mike
1 Cary
2 John
2 Mike
2 Lester

So, if I enter 1 into the reference cell, I would want a list to say John, Mike, Cary....if I enter 2 I would want the list to be John, Mike, Lester.

There can be multiple values of the same Manager per pool, but I just want a single output of the manager name.

This is going to be based on a list of over 1,000 rows, and 30 different possible pools. Please advise, and let me know if anything is unclear