What if the Grounded debuff was added to Karthus as well?
Right now, Cassiopeia is the only one with that debuff (surprisingly Taliyah's traps don't have a Grounded debuff on them, albeit being dash-sensitive). So, what if we added Grounded to Karthus' E? It would help him a bit, and it would reinforce the fantasy of battle mage/come near me lategame and you just die.
and
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