If it's plain, it means that it's likely an original one , as the reflection holo stamp is printed directly on it
Youre allowed to use any other form of randomization as long as each player involved in the game agrees to it
It gains hexproof until end of turn
If you class things like Maelstrom Pulse as a modal card that just has four modes on a type of permanent to destroy, and the same for the cycling Disenchants as they have a draw card mode then basically all the good Disenchants for cube use are modal
The shaves to the typical manabase likely form some combination of Ancient Ziggurat or Unclaimed Territory for a Sunbaked Canyon, and possibly the Island for the Waterlogged Grove, but I will need to go into the lab to figure out the right formula
But there are also cards that target one other creature, like Artificial Evolution