Fatal Weakness
3
Plot Twist
Play only during your attack step. To play, stun two Revenge Squad characters in your front row. KO target character if its cost is less than or equal to the combined cost of those characters.

Can you attempt to use the 2 drop Mr. Myx from Man of Steel in addition to some other character to satisfy the cost of this card?
It would put the "Stun this character" on Myx, but would fail to resolve. I can see how this could go either way...but Am thinking I'm in the "No" camp on this one...

No - if the cost can't be paid, the effect doesn't happen...and the stun is a cost.

Yes - you can use him - the effect goes on myx but it doesn't happen because of his card text - the trick still works because there is no "If you do..." clause.

help is appreciated - Either way, ahmed and the checkmate kings just got a big fat bullseye on their heads....

Nope, can't do it. Since it's a cost, it must be paid by stunning two characters. You can't "put the effect on him". It's not an effect.

rats...still - that's what I expected...
still powerful. Stun your 2 and 3 (but with some gross vengance effect) to ko their 5, then swing down with your 5 and 4....