kde-base/atlantikdesigner-3.5.1 depends on kde-base/libkdegames-3.5.1, but ACCEPT_KEYWORDS="~x86" emerge kde-meta --deep --tree -a would try to emerge it before libkdegames.
Uh? `emerge --info`, missing. Also post the relevant emerge --tree output as well, please.
No feedback and not reproducible.