"While you are not able to serve men, how can you serve spirits?...
While you do not know life, how can you know about death?"

   – Confucius

Spirit Speak is one of those long forgotten skills that have finally been given a purpose in life: speaking to those that lost theirs and feed off the energy from the hapless corpses of the defeated. It also increases the power of your necromancy spells, just like evaluate intelligence increases the power of magery spells.

If you have been in a combat and suffered HP losses, you can use this ability to regenerate some of your HP. If there is a corpse lying nearby, you will channel the energy from that corpse into your own and restore your health. In order to feed off the dead, you have to be standing within 3 tiles of their corpses. If there aren't any corpses nearby, you will use your own spiritual energy (i.e. mana) to restore some HP. You require a minimum of 10 points of mana to be able to heal yourself using your own energy. One of the main upsides of Spirit Speak is that you can restore HP even through poison. It is therefore highly recommended for people who PvP a lot as well as people with no Magic Resistance that fight high level spellcasters.

Training this skill is simple and straight forward. Hop on a boat, and use the Spirit Speak skill until you're blue in the face. And just do 8x8. You can buy the first 30 points from NPC Healers