Various sources have had a stab at sorting out just exactly what DRs with what else, but there is so much mixed messaging and conflicting information out there. I was researching it for a column, and struggling, so I dropped PvP Designer Brian Holinka a line on Twitter. He came back saying that he'd try to get the CM team to put something together, and he's a man of his word. Community Manager Lore just posted a summary of just what DRs with what.
How do you use it? Well go on over to the forum thread he made, do a CTRL+F of the spell you're looking for, and you'll be able to see what it DRs with. If you want to look at specific categories, then follow the links in the first post.
This is a truly fantastic resource, and it's about time there was a definitive source of this information. But my god, there needs to be some optimization done in this system. It's insanely huge and confusing and hard to remember. Stick with your own spells at first, when you're working out your comp's CC chains, and worry about the rest as you go!
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