I havent played it for ages, but Im going to give you my thoughts about it now
excavate the top cards of your Deck, equal to the number of monsters in your GY (or as many as possible), and if you do, if 2 or more monsters were excavated and all excavated monsters had different names, add 1 of those monsters to your hand, also place the remaining cards on top of your Deck in any order
As this card will be legal in Standard for at least the next five years, having a board wipe card like this was an unexpected addition
Beast Within is a very nice flexible removal spell that can handle things that green can have trouble handling, so getting a new Beast Within color-shifted to white is definitely welcome for Commander
return that monster to the Extra Deck, then you can Special Summon Level 2 or lower Beast monsters from your GY, up to the number of materials that monster had