­Camouflage + Eternal Forest

Gibber. One of the cards that got dropped back when power9 was banned. In this case, though, primarily because of its complexity. More or less - defending player chooses which creatures will block (and can say "These two block together" etc.) but can't choose what they block, that's randomised.

And a forest that you can't destroy.

So clearly the flavour mash here is hiding in the trees.

I just came up with "Treefolk have forestwalk. (Because they're walking forests, duh)" But that's probably not good enough.

Camoflage can very nearly be re-written as "After blockers are declared, before attackers are blocked; each blocking creature blocks a random attacking creature."
That loses the 'groups' concept; but banding is long gone, so probably ok.

Not sure where trees fit in there. ... Oh hey, I've got it, we'll combine with Living Lands.

Lost the indestructible part, mostly - but it's sorta there by having the forests get blocked instead of your good creatures.

Rarity - rare rare rare. Cost? It's a finisher.. wild guess at about CMC 3. Colour heavy, which won't really matter since you'll want to use it with lots of forests anyhow; but makes it seem shinier.

Huh, there don't seem to be any recent 'animate lands for a turn'. I was thinking this might be too good; and would encourage you to just swarm rather than using the camouflage bit - maybe make the lands 0/1 instead of 1/1. Yeah; let's do that. It justifies the lower cost.