While Vital is a "wavetable" synth, it is widely considered the best free synth on the market right now. Because it is so versatile, you can find countless community-made presets (via the Vital website) for "Dark Pads," "E-Pianos," and "Plucks."
These plugins provide the "underwater" pianos and thick 808s that define the genre: trapsoul vst free download
If you are starting from zero, download these five free tools to cover all your bases: While Vital is a "wavetable" synth, it is