A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
A player, 11 October 2011
Thunder's wrath Battle: Destroy this card: Ranged 4 Attack with +2 strength if it targets a Follower. If this Shugenja is Thunder and the Ranged Attack destroyed a Follower, Ranged 4 Attack.
Iron will Reaction: After another player targets your Paragon with a Battle action performed by a Personality with lower Personal Honor: The action's costs are ignored and its effects are negated. That player may take an additional Battle action.
What happens if I destroy a follower with thunder's wrath(and the shugenja is Thunder), and then I target the personality with the second ranged 4 attack, and my opponent reacts with Iron will? What happens to the follower? and If it's a follower token?
Thanks and regards
Alex Jones (rules official), 11 October 2011
Thunder's wrath Battle: Destroy this card: Ranged 4 Attack with +2 strength if it targets a Follower. If this Shugenja is Thunder and the Ranged Attack destroyed a Follower, Ranged 4 Attack.
Iron will Reaction: After another player targets your Paragon with a Battle action performed by a Personality with lower Personal Honor: The action's costs are ignored and its effects are negated. That player may take an additional Battle action.
What happens if I destroy a follower with thunder's wrath(and the shugenja is Thunder), and then I target the personality with the second ranged 4 attack, and my opponent reacts with Iron will? What happens to the follower? and If it's a follower token?
Thanks and regards
The action's effects are only negated after the Personality is targeted, so the follower is still destroyed, but the second Ranged Attack is negated.
See Effects, Duration and scope of prevention effects: Prevention of instantaneous occurrences is never retroactive. Specifically, if “all effects” of an action or trait are prevented partway through the action or trait’s resolution, instantaneous effects that have already resolved are not undone.
Note that destruction is an instantaneous effect!