Thunderlord’s Decree is not only the most popular Keystone mastery in League of Legends but also the most broken one of the lot.
It works differently for every champion. Lux can trigger Thunderlord’s Decree by first landing her Q (Light Binding) and then auto-attacking to proc her passive (Illumination). However, the same method doesn’t work for Varus. Him auto-attacking and then using a skill to proc his passive (Blighted Quiver) fails to trigger Thunderlord’s Decree. On the other hand, Morgana can easily get the Keystone mastery to work through just her W (Tormented Soil).
Responding to a recent thread on the official League of Legends forums, Riot Games admitted that Thunderlord’s Decree is broken. According to assistant game designer Riot Fizz Enthusiast, the Keystone mastery is unable to distinguish between the types of damages.
“The system in place currently can’t tell what types of damage are causing the Thunderlord’s to pop, and that it only reads damage indiscriminately—that’s what’s causing the discrepancies,” he explained.
At the time of its release, Riot Games didn’t have access to the necessary technology to make the mastery work right. Hence, it has remained so. As such, the developer has been aware of the issues from the beginning but unable to fix it.
However, Riot Games is close to finishing the required technology that will introduce a new system for Thunderlord’s Decree. Through this, the Keystone mastery will be able to differentiate between all types of damage.
How will this effect champions?
There’s bad news for certain mages. Champions like Morgana who can trigger Thunderlord’s Decree with a single spell will no longer be able to do so. Any spell that damages a target more than once will be counted as one in the books of the Keystone mastery. The same goes for Brand and his burning passive (Innate). However, champions like Zyra who do sustained damage through her plants will still be able to do so.
One thing’s certain, the new Thunderlord’s Decree system will change the meta of mages in both mid-lane and support roles. It’s possible that Riot Games will improve the other Keystone masteries to give us better alternatives.