Longest possible CC chain on healer? (while taking dmg)

[Dactylion-frostmourne (Dactylion)]

Take your pick from each of the categories

Crowd Control & Diminishing Returns

When you’re affected by a crowd control effect in PvP, there’s an 18-second window for diminishing returns on further effects from the same category. Additional CC effects used on you while diminishing returns are active are reduced in duration: first by 50%, and then by 75%. Each CC effect resets the 18-second window to its full duration, and if you are affected by three CC’s of the same category inside that 18-second window, you will be immune to further effects from that category until the 18…

ie.

Kidney > Cyclone > Polymorph > Silence

Wouldnt work in Arena (because this is from four different classes), but in a BG the above would be a CC chain of around 22 seconds without DR.