Overgrowth Big Beasts

In white, angels will represent the top end, probably power/toughness no greater than four.

Here are the top-end monsters in the remaining colors.

There are no vampires or demons on Guthreham, thanks to Janell. But there are dragons, and the spread of diseases in the overgrowth occasionally infect even them. So there are zombified dragons as a result of the plague and not through dark necromancy.

Edit: Just realized I templated it wrong and it should require you to sacrifice all your creatures. I don't know why I made that mistake.

Note that the bounce is a must, not a may, part of the general "out of control" feel of the set. In this case, though, it's not as likely to backfire unless it gets out onto the battlefield abnormally early (which could happen). I'm trying to decide if it's okay that it hits lands. I think it is. Heck, if I go with the decaying dual lands concept, it's a way to save your own.

I was way too impressed with myself for coming up with this name. And then I did a Google search out of curiosity and found out it's already the name of some cross-country foot race. Nothing new under the sun. The name has flavor meaning here: Surrounding The Arbor are six rural regions known collectively as The Acres. Each one is named after a species of tree: (Juniper, Alder, Oak, etc.).  Janell named all these districts and planted the trees they're named for after they won the war. Unfortunately, the overgrowth has made all the acres very dangerous places to live from all the mutating beasts. The trees she planted have spread and overwhelmed the pastoral communities. The guards of The Acres have to patrol constantly to try to keep creatures like this from reaching The Arbor and threatening lives.

As with mechanics like raid, revolt, and explore, most creatures and spells with reave on them will trigger only once, typically as an enter-the-battlefield effect. The Nightscrape Sovereign will be one of the few exceptions, but I've still templated it to happen only once, and any recurring use of reave will be templated to happen only once per turn to avoid absurd game-breaking combos.

Note again that this is a must, not a may. This guy can backfire on you if you're not careful. Pun intended.