(I guess this has already been reported, but still not fixed about a month later!)
According to April 30th patch notes retaliation should do same damage in as in spvp in WvWvW. But this seems to only apply to Eternal Battlegrounds. Retaliation does full damage on Borderlands.
https://forum-en.gw2archive.eu/forum/info/news/Game-Update-Notes-April-30-
2013/first#post2014472
Retaliation still bugged in WvW Borderlands.
Another earlier post here:
https://forum-en.gw2archive.eu/forum/support/bugs/Retaliation-bugged/first#post2023697
Still no fix for this bug in the latest patch?
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