Simply use the image upload feature in the body of the post and you can attach as many images as you need. Below is an example of that.
I’ve placed images in a spoiler so they don’t clog up the post, they are all SFW images taken from various community icons.
Click to reveal images.
The devs really ought to work on a way to properly show multiple images from a link like the way that Reddit does. I hate having to upload images individually when I want to link a post that has more than one image.