The OVA starts off with a live-action opening of some, at least attempted, creative filming using models of the actual leading mechs that are seen in the OVA. The after-credits shows the process of them creating the model-replicas that seem to actually be almost the size of a person. It was interesting, but it was clear that this was still an anime studio as the filming equipment was pretty low quality and the camera movement felt a tad amateur. That might add to the experience for some people though, so that'll end up being a subjective call.
I would actually say that the junkyard aspect of this OVA does come with the expected result of having designs that wouldn't work in reality, even though the models seem to be able to stand. The villain mech would clearly never have been able to stand if translated to real-life as it was shown in the animation. It can be noticed in the animation counterpart that the torso is basically a twig, while the model-version has a much thicker torso which allows it to barely stand while almost tipping forward (which you can notice from the model's head not being able to lift properly). My claim doesn't direct only at the main mechs though, but everything as a whole. The design-work is impractical, but that doesn't need to be a negative as it should basically be expected when going into junkyard sci-fi.
The art is, again, pleasant with an old looking style that's a tad colorful with a good amount of detail lines. The detail lines added are in large numbers and give everything a rough feeling, making the clear-cut characters feel very contrasted to the world around them. There is also some fair animation and some consistent proportions to basically everything. There wasn't much cool moments of fighting, but there was action to a somewhat small extent.
The story is pretty bare-bones with there being an evil, imperialistic nation that wants to take over the world, while a girl finds a machine and simultaneously protects her city. It never was clear to me whether her goal was to protect her city or to simply fight with what she discovered, however. The other character is actually the mech she finds which has built-in A.I. There wasn't exactly engaging dialogue between the two characters, but the characters fit the setting in its pleasant atmosphere making it easy to enjoy the company of the characters. There's also a lacking amount of human faces shown here, mainly only the girl being shown. The human girl brings some relief in that aspect to serving as the contrast to the metal and war-torn world around her. The ending to this story isn't really an ending to everything, but to a single issue that was occurring in the character's pasts. The conclusion to that element is pretty anti-climactic and also makes the final words that were spoken quite comical and cheesy. Even so, the story wasn't really the driver and wasn't really required to do much in such a small run-time.
Dragon's Heaven is a junkyard, sci-fi short that is based around mecha. There isn't much cool fighting moments to be had though, while there certainly are a few times where shots are fired and explosions are made. The story is a bit basic and dry, but the setting makes up for it with being a tad refreshing in its simple goals. It also adds to the enjoyment knowing that so much work and passion went into this little OVA down to the creation of the models. Even if one isn't too impressed with the designs present here, it's hard to not feel a little joyed to see how the people behind this OVA felt very highly of it. The soundtrack is also orchestrated and done wonderfully. It all totaled into an atmosphere similar to something like "Dragon Heart" while being an anime in a junkyard sci-fi setting. Dragon's Heaven is so short that it shouldn't require too much risk to give it a shot, but the visual style might look "dated" to some who can't handle older titles. If that isn't a problem, try this one out.
