Destroying object after animation

i know there was a lot of topics with destroying after animation problem, but i did read them all and i didn’t get anserw i seek.

My project:
2D game, scrolling like, platforms etc.
I have portals that appear on sky, spawn monsters and dissappear.
I took one series of images, sliced it and made 3 animations (by selecting group of single images and drop to scene). This way i did begining animation, middle animation (it will be reapeated random number of times) and ending animation.
From middle animation there is a trigger, if code trigger it animation goes to end animation.
I made a transition between them, and from ending animation i made transition to “Exit”

First of all, i wish to make it not repeat after ending animation (i mean, even when i did transition to exit it is start over again from begining after end.)
Second problem is title one - destroy after ending animation ends.

I did try some of others ideas, but somehow i can’t get my animations into animations editor to make an event. I can’t get length of animation by animator.

well up to what i understood you can use addevent(one option from animation window).
I mean think like your sprite having one animation. At the end of last frame (or where ever you want) you can use addevent option that is appear at top of the “samples” option(it is a symbol having plus at the bottom).
just know about use of that one .

it’ll useful to you.

The thing is, i can’t open my animations in Animation Editor (as i wrote before)
I can’t open (or i am doing something wrong) in animation editor any file that was created when i drag and drop series of image to scene (made a new animation).