I played a bit with elf/zombie/necromancy/leech combo and noticed some odd interactions.

1. Healing out of combat with blood surfaces is near impossible as they disappear once you walk over them. Unlike blood, poison surfaces seem to disappear after a set amount of time, regardless of you travelling over them to heal.

2. Dealing vitality damage while having points in necromancy hurts the caster if they're a zombie. This also creates a pool of blood which can be used for leech-healing.

3. Cannibalizing a corpse as a zombie elf hurts the consumer and is potentially deadly if not treated with excessive dosages of poison walking.

Non-related bonus: With Far Out Man you can damage enemies outside their detection range. They will not engage in combat immediately but you will be suspected for assault.