Spellshield of Malekith question

[Lord damian valar]

I have a question regarding Malekiths spellshield when fighting Tomb Kings.

When you succesfully dispell a spell from a tombking caster, what happens? Does the caster suffer a str 6 hit for every die he rolled? Or does he get only 1 str 6 hit just like bound item spells? Does the spellshield work at all?

Also, what about dispelling the Casket of Souls with the spellshield? Does the Lichepriest on the casket get the str 6 hit or the casket itself?

Thanks in advance...