I don't know if you're running amazing teleporter or not but what I've found certain things that make them randomly jump out.

1) If you're running amazing teleporter and TP somewhere while in the air, it'll look like they are on ground when you dismount but it still registers them as "flying". So before teleporting, just land first then teleport or fly then land and it should work.

or

2) If you recently killed something close by while your wyvern is on attack your target / neutral / aggressive, it will kill the last thing that still has the corpse. Try putting it on passive.

im more worried about the fact theyre just a bunch of square blocks lol

Oh, they will be square blocks but in the eternal workbench, there is a costume that removes that effect.

no kidding? cool