There are clerics who have turned to worship the gods of Chaos and Darkness, but I am here to tell you about the more natural path of using a cleric's powers. I have not yet gained my full powers, no, far from it. I have studied the subject, though, and what I can't tell you right now I can find out soon enough. Now where was I? Ah, yes. A cleric's powers are mostly defensive. We can heal ourselves as well as others, slow and remove poisons in/from the victims' veins and, when experienced enough, even cure the horrible plague. Even the least experienced cleric knows how to shed light in a dark room. A mediocre cleric can ask the Gods for protection against cold or fire. Removing curses from items is rather easy, blessing them is much more difficult. We can also reverse some of the prayers, a healing prayer turning into one that creates wounds on the foe "out of thin air" and a blessing becoming a curse. Should a cleric walk into an undead creature, it is possible, with the help of the gods, to turn them away from attacking the cleric. Of course, you must have some experience or you just might end up drawing them to you instead of eluding them.
You wish to see something? Hmm. And you won't settle with a holy symbol glowing light? Hmm. It seems that you seem to be in good shape as well, so the effects of a cure wouldn't show. Let me think now...
Fir holds her holy symbol in front of you. "You might not see it, but by the powers of the gods I see that you have created a small resistance against magical healing. They don't heal you as effectively as they once did. I see a dim haze surrounding you. That is the sign of a very mild resistance. A cleric can remove it, as you may have guessed. I shall purge it from you, if you wish."
You nod. Being a person who frequently uses the help of magical healing potions, you know you could use it. The cleric holds her symbol tightly and prays silently. Then she reaches her hand to touch your chest and pulls it slowly back again. A thin gray mist follows her hand, pouring forth from inside your body, continues down on the floor and dissipates. Finally, she seems to check your body's resistance again.
She frowns. "This shouldn't be here...", she mumbles to herself. "A
misinterpretation?" She double-checks. "Oh. It seems that your addiction
is stronger than I suspected. Brace yourself. This won't be nice."
You shrug and stand straight. Fir produces a small potion from her pocket.
You notice the label, "Mental recharge", just as she quaffs it with one
gulp and shakes her head quickly as it takes effect. Then she holds her
symbol in her tightly clenched fist and prays in a determined voice for a
while. She touches your chest with her symbol, and this time you see a
dark grey mist emanating forth. You feel like she was pulling your
intestines out through your chest with it. When the prayer is finished,
you feel dizzy. The cleric isn't that healthy-looking, either. Her face is
pale and she sits down. With a wave of her hand she invites you to listen
carefully, then speaks silently: "This particular prayer is very draining
to both the prayer and the one it's used for. I'll be needing some rest
now, if you'll excuse me."
You nod again and leave. Your chest still aches a bit, but you feel purified.