#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

my @strings = qw( He_is_super_hero_Spiderman
                  He_was_a_super_actor_Tom );

for my $string (@strings) {

    my ($spiderman_or_tom) = $string =~ /Spiderman|Tom/g;
    say $spiderman_or_tom;

    my ($last_word) = (split /_/, $string)[-1];
    say $last_word;

    my ($last_capitalized) = $string =~ /.*([[:upper:]][^_]+)/;
    say $last_capitalized;

}
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Update: Explanation of the second solution: negative indices count from the right.
Explanation of the third solution: .* matches as much as it can, then it captures the word starting with an uppercase letter and continuing with anything but underscore.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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