my friend took over 12 grams and said he didn't feel much other than being a little more chill. He though it would be more potent but it wasn't and was disappointed. Took them in powder form no tea.
Its supposed to act like an opiate and I have heard it can be addictive. Not nearly as addictive as opiates in that case its shown some dependencies with some people, so just keep that in mind. Marijuana is way better from the sounds of it, I may try some though and see the effects and report back.
If you want to turn black. Take high volumes of Kratom over a long period of time.
"Kratom is not known to be toxic, but it can be quite unpleasant at high doses, causing nausea and vomiting. Regular use can lead to physical dependency. Kratom use can cause constipation similar to that caused by opiates. Chronic heavy use is reported to cause darkening of skin, insomnia, dry mouth, and anorexia."