Gonna do my best here with the drow arachnomancer, but please forgive me if I screw up, like, half a dozen different things. I’m operating with two levels of exhaustion, and I’m not even the one doing most of the work. My wife is a boss.
Arachnomancers are drow warlocks that can shapeshift into or out of a Large giant spider form as a bonus action and can continue to speak and cast spells in their spider form. Because they’re warlocks, unlike most monsters with spellcasting ability, they cast all their spells as if using a 5th-level spell slot, but they’re also limited to three leveled spells per encounter (not counting darkness, dominate monster, etherealness, eyebite, faerie fire and levitate, each of which they can cast once per day without spending a slot, and dancing lights, which they can cast at will). Concentration, of course, is going to govern which of these spells they can cast, so we’re going to look for sustained spells that synergize with multiple instantaneous spells.
Also, since these are warlocks we’re talking about, we want to find out what works well with eldritch blast. Although it isn’t stated explicitly in the stat block, because the drow arachnomancer is a 16th-level spellcaster, eldritch blast fires three bolts per casting, for a total of 3d10 force damage. In terms of damage dealt, this can’t compete with either its humanoid-form Poisonous Touch attack or its spider-form Bite attack. However, based on its ability contour—extraordinary Intelligence, very high Dexterity and Charisma, merely above-average Constitution, average Strength—we can infer that the arachnomancer is a long-distance spellslinger that would much prefer to stay out of melee if it can. Thus, Poisonous Touch and Bite are primarily self-defense measures, secondarily shock attacks. Continue reading Drow Tactics: Arachnomancers