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.
In viewtopic.php?f=59&t=111163 it was ruled that when combining attacks, each attack gains applicable blanket modifiers, even when used as an interrupt.
In viewtopic.php?f=59&t=109789&p=1438807&hilit=combining#p1438807 , it was ruled that when combing attacks, attacks combined as interrupts do NOT receive blanket modifiers, as they are only bonuses to the original effect.
Which is correct?
In viewtopic.php?f=59&t=111163 it was ruled that when combining attacks, each attack gains applicable blanket modifiers, even when used as an interrupt.
In viewtopic.php?f=59&t=109789&p=1438807&hilit=combining#p1438807 , it was ruled that when combing attacks, attacks combined as interrupts do NOT receive blanket modifiers, as they are only bonuses to the original effect.
Which is correct?
Both answers are correct.
The trait on Streets of the Second City modifies each Fear effect, whereas Legulus' trait only modifies Ranged Attacks that target him.
For a more direct comparison, consider targeting Legulus with two Ranged 3 Attacks while Higher Ground is in play. The blanket +1 (if it's your Higher Ground) or -1 (if it's your opponent's) to strength applies to each of the Ranged 3 Attacks. However, only the original attack targets Legulus and gets -3; the Ranged Attack effect from the second merely modifies the original attack and is unnaffected by Legulus' trait. So, Legulus will suffer a Ranged Attack with total strength of either 5 (= 3(original) + +1(Higher Ground) + -3(Legulus) + +3(combining attack) + +1(Higher Ground)) or 1 (= 3(original) + -1(Higher Ground) + -3(Legulus) + +3(combining attack) + -1(Higher Ground)).
Higher Ground: Your Ranged Attacks have +1 strength. Other player's Ranged Attacks have -1 strength.
Legulus: Melee and Ranged Attacks targeting cards in this unit have -3 strength.