2 MTG: Magic The Gathering questions?

Last Word can be stopped by Shunt, Fork, Swerve, Willbender, Misdirection. Anything that allows you to change the target of the spell, but something else needs to be on the stack. Best bet is to get in a counter war and hopefully he plays last word, last. Then you do one of the above spells and target one of his earlier counters already on the stack.