Been super busy lately, but I've finally got more than a minute to rest and this kind of stuff is relaxing for me, so...
When Kori reaches 4th level, he will automatically learn Cure Moderate Wounds and Invisibility. He'll also learn a 2nd level spell of our choice, plus a Darkness-related or Shadow Illusion spell from the Sor/Wiz spell list thanks to his Dark Secrets Revelation.
Right now he knows Shadow Trap because of Dark Secrets, and that's the closest thing he has to an offensive spell. At 4th level, he can choose to lose that spell, however, in order to learn a new one along with the spell he would normally get from the Revelation.
Searching Shadows is a very versatile 2nd level spell that can do a lot of things, both in and out of combat. I think it would make a good replacement for Shadow Trap in part because it seems kinda like a direct upgrade of the spell. It's got longer range and more functionality, but on top of that it can completely immobilize a target that fails their save, so long as Kori concentrates. Shadow Trap Entangles a target and keeps them from moving far, but they can still fight and cast spells. Better yet, the spell lasts until Kori stops concentrating, so he can switch to another target if the first is dealt without recasting the spell. With its longer range, he can hide out of sight using stealth and ruin people's day.
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His other new Dark Secrets spell should definitely be Darkness. There's too much synergy with our party to overlook the spell. Everyone but Gorok has Darkvision and he still has Low-light Vision, so Darkness will get us a lot of mileage.
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That leaves his new Divine spell to select, and that's where I think it's time for him to learn an actual offensive spell that can inflict damage. There aren't many good 2nd level options on his spell list, but there are a couple of nice standouts, IMO.
Boneshaker is a single target spell with decent damage (5d6 at 4th level) and good range. I'm addition to the damage, however, it also comes with some other neat options. Against a living target, you can make them move five feet. That doesn't sound like much, but positioning is super important for melee combat and it can set up good combos for Gorok or Cob to exploit. Against Undead, the options are even better, forcing them to move up to their full speed or attack another creature within reach.
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The other standout is, ironically enough, Burst of Radiance. For a Shadow-themed caster with a weakness to bright light, this one comes a bit out of left field. The damage isn't anything special (and it only hurts Evil creatures), but it's a solid AoE with long range and it can blind everything in the area. Even making the save Dazzles a target, which lowers their attack bonus, and the damage is unavoidable for Evil targets. An AoE blinding effect is really powerful, especially for our group.
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