This was not fun to read though. I'm going to tell you my opinions on the parts that bugged me the most, kay?

Applejack dashed in, shortly followed by Twilight, Rainbow Dash, Rarity, Spike, Pinkie pie and finally Fluttershy. He yelled "Oh fuck!" as he took off further into the depths of the library, Applejack not far behind. Before anything could be said, the tree then shook with a massive audible 'Thud!' Applejack said "I got 'im!" He cried "No fair! I WANT A DO-OVER!" Fluttershy quickly became spooked by the sound of tussling in the back of the tree, Twilight ran up into the room that Adam and Applejack were in. Twilight approached Adam, he squirmed underneath Applejack and said "Get off me you fat ugly CUNT!" (I would like to note that on the behalf of all new people that Adam will often refrain from swearing if he can. However, he will never say cunt to anyone, especially not his worst enemy.)

Now, I haven't read your other story, so if I'm missing something I'm sorry. But, this is rather, weird. First off, why is Applejack so bent on attacking Adam? This all seems a little bit rushed. Also, why are you talking in third-person and first-person? Don't do that, please. And you said that he's not going to say "cunt" to anyone, even though he said it? Consistency? What's that again?

Twilight said "It appears so Applejack, but why would she only want him, why not come for all of us, surely he alone isn't powerful enough to fuel her army?" She said this with confidence, but had even doubted herself. A Human that had four forms, one who could command the forces of magic with such strength should have been supervised and had constant checks made upon them. Adam was one of those dangerous yet interesting unknowns, one with the ability of cross-dimensional traversal was considered to be a god, even by unicorns standards it was rare for one of their fledglings to gain such abilities.

No. Please no. Reading this makes my say that this "Adam", who wasn't even there, mind you, is a Gary Stu. Heck you even said that someone with those abilities was considered a god! BAD.

One: If there are humans in ANY part of your story, it needs a human tag. I don't see one.

Two: if he's so strong, WHY WAS HE CAPTURED? I'm sorry, but that aggravates me. If he has a major flaw that can get him captured, good and fine, but you made him sound like he's Celestia and Luna rolled into one. And you said that Chrysalis captured him? Bull. Chrysalis was beaten by the power of love, I get that. But you're saying that Adam has FOUR forms AND one of them has a extreme grip on the power of magic. How in the h*ll did he get captured?! Please, have a damn good explanation for this, or this won't end well for you.

All the ponies of ponyville knew Mada well enough to know that a 'Mada' promise was binding, just like Pinkie's only to the next extreme, if the pony promised and then forfeited the promise, he would bond them up in his house and proceed to form hardcore sexual acts upon them relentlessly for the next week. Many ponies made Mada promises because he was a loose cannon, sometimes ponies even volunteered to be captured by Mada, he laughed as he always got the ponies to near orgasmic point and then denied them the opportunity to experience their own hot liquids gushing pleasurably out of them.

What? No, I'm serious, what?! What the hell?

Okay, I don't know who this pony is, but...he needs a backstory. Now. Why is he Adam's alter ego? What happened to make him like that? And please for the love of Celestia...explain what the heck I just read. This....this part wasn't even needed! I honestly have no idea where this would be used in your story. I know that this is rated Mature, but, I don't understand......

He wiped a tear of laughter from his eye, it solidified into pure diamond, Rarity gasped but didn't do anything else. He flicked the tear shaped diamond into his hoof, then handed it to Pinkie, he said "My one act of kindness to you, use it whenever you want, just press it between your hooves, make any wish, it'll come true. That's for making me laugh my fucking ass off." he chuckled slightly as he walked out the door, leaving the entire crew gazing at Pinkie with awe and a hint of jealousy. It was rare for Mada to consciously do any good, once a day he did one extremely brilliant act of kindness and selflessness to 'balance out' all his acts of evil, somewhere inside of him lived a fragment of Adam, no matter how small, it affected him hugely.

Tear+ turning into diamond= What, is guy just as strong as Adam? Because if he is, then you have TWO Gary Stu's. One is bad enough. And this diamond tear grants wishes? Why?

As happy as I am that this "evil" character did some good, I'd rather it made sense. Also, one act of kindness isn't going to balance out acts of evil. There are very few times where I've seen that work well. This is not one of them.

I will give you points for using capitals and mostly having your paragraphs spaced well. I went though at least two stories today that did not have those. Remember that when another person (or pony) talks, it starts on a new line. Always.

My final advice. Re-write this. Add some backstory, and some more development to Mada. Simple stating that he's an evil sex-driven pony doesn't help. I wanna know his thoughts, his goals, why he does what he does, what his plans are.

And make Adam weaker. Seriously.

That's all for now, but I'll check out your second chapter later.

From a brony just like you,

twow443, TWE's Knight in Training

this sounds goofily fun. on to the next chapter.