They give everyone 15 agility, and you can train it with barbarian fishing. And i guess that's how you're supposed to get 99.
There are other ways to train agility without spoiling haha.
This whole discussion thread is amazing and every time someone has told me one relic is a nobrainer I can give an example why the others may be better.
I look forward to seeing the numbers for which ones people pick when it gets released