kinda wixh you can apply this to plants to get Biollante. granted i imagine you can bend the rules a bit with any template, i believe you already did yourself with a previous one, but still.
i wonder if the lich template is up next, i know mummy, wraith, ghost brute, and wight templates are on the table as well. now to think about it there are a lot of undead templates
i feel like it should state the guardian has to be bloodied to get elite recovery like other elite monsters.
Also Teleport should be an action and not a trait.
since the puzzle golem can go up to large size, maybe make variants that can go up to titanic (who i imagine being the elite version of the gigantic variant). The web golem/web guardian is also a thing from that issue as well.
While i do suppose we're gonna deal with the fiend dragons eventually, from the same issue there are also mummy, wraith, ghost brut, and wight templates from the same issue. We already did a bunch of skeleton templates awhile ago so why not.
i think that blood horses are meant to be fallen celestial equivalent to pegasuses (note how all the fallen angels still keep the celestial tag but are still evil).