Guide Weak point on the Charred Warlock?

Trying to be efficient about the Charred Warlock. Its listed weakness is weak: Spirit; resistant: Pierce, Frost; veryresistant: Fire; immune: Poison and its threat/profile is Ashlands creature. Is focusing the weak point the whole fight or is there positioning I'm missing?

Saving this, genuinely. As a newer player this is exactly the kind of thing I needed spelled out.

Yeah the Charred Warlock is exactly as you describe. Good call starting this.