MArcomage

In my opinion, this just makes Emissary too easy. It's powerful, but its drawback is that you can only effectively deploy it in a few specific situations. Having it handed to you makes it overpowered.

Raised the cost to 18/18 so the whole combo's cost is 30/30 for a maximum of 70 attack

That nearly brings it in line with other Uncommon Undead attack cards, I suppose. I'd consider making it either cost a little more or removing the Undead keyword, however, as it's likely someone would trigger the keyword effect while playing it (since you only want to play it with several Undead on hand and thus will gain a lot of tokens) and have 6/6 refunded.