Trope Trasher 2

There are two types of SI, the Replacement and the OC. Replacement SI's put their minds into the bodies/positions of the fictional character and OC SI's introduce themselves as a completely separate entity.

I awaken on a cold sterile table; a voice rings in my ear ordering me to put on my armour.

At a glance I find I am somehow inside the Mass Effect game series. Why I haven't fainted in shocked denial, I don't know. How I'm even there is an even more mysterious, probably some sort of otherworldly intervention or space magic… maybe a magical X-Box.

I know this is Lazarus Station; I've somehow replaced the legendary Commander Shepard.

This is incredible, despite the fact I have none of his experience controlling a body his size and weight and no idea what my first name might be the opportunity to charge into battle against merciless killing machines is too great to pass up.

I reach into the cupboard and retrieve the N7 Armour stored inside.

I realize quickly that I have no idea how to put this stuff on.

It takes me half an hour to figure out how all the while listening to Miranda's constant whining as I do so.

Well, I'm not romancing her that's for sure.

I step outside the room ducking behind cover.

I know that a Loki-Mech is about to come through that door I turn and take aim.

The bullet goes through my left eye.

Apparently shields only work if you know how to turn them on.

That's the Replacement SI; now flinch in horror at the OC SI.

I appear on the Citadel, mysteriously.

I have no idea how I got here, I have no money, my clothes are over a hundred years out of date, I have no identification and yet I fit in perfectly.

There are aliens all around me yet I understand every word their saying.

I am somehow thrown into a completely random series of events slap dab in the middle of what I know to be the Mass Effect games; this of course is an incredible realization that doesn't faze me in the least.

Somehow despite never using a gun before I have become the greatest marksman that has ever lived. I instinctively know how to put on armour and use it effectively. The Omni-tool, which was somehow implanted into my skin without my knowledge is easier to use then a Smart Phone. I have manifested Biotic abilities that far outstrip those of any other being in the galaxy.

Oh, and women/men love me, regardless of species or previous sexual orientation.

I have knowledge of events past, present and future that by all rights I have no business knowing. No questions are asked when I reveal this information, despite most of what I'm saying being beyond restricted if not impossible to know simply because it hasn't happened yet.

We continue through the events of the game, deviating minimally and yet saving every life we come across for no apparent reason other than we can.

We conquer the Reapers without any casualties, not counting the billions of dead Reaper troops who were at some point living and breathing beings.

All is well and everyone lives happily ever after, except the billions of dead people I've happily overlooked.

Self-inserts. Yes. Those. Every author out there has dreamed of meeting, being, or banging a fictional character, be they their own or the works of others. Considering how sexualized everything is nowadays that's really not surprising.

The point is though, a good self-insert is well structured, in depth and uses applicable data to form a well thought out plot with a believable character progression. A bad self-insert introduces an everyday, average, man, woman or child then turns them into all-knowing gods of war with the ability to cure cancer with their tears and shit gold bricks.

This also relates to argument laid out by the previous trope as your SI's presence is a giant foot up the butterfly's ass. Your presence is variation, what is not meant to be there suddenly is, thus every previous reaction is now moot because an extra factor has been introduced. 2X2=4 and 2X2x2=8, the math isn't quite that simple but the underlying equations are there.

Throw in the fact that I got sick of typing 'I' while writing this and I'm left wondering just how conceited you'd have to be to write a story where the universe seemingly exist around you. No offense meant to those few authors who are actually good at writing SI but even they have to ask the question, do I really think the universe revolves around me?

Oh and before I forget. Mary Sue says what?