Its like a Genesis Hydra that you have to cast for X=5, and it only works if have a graveyard full of creatures, and its a little more restricted in what it can find, but it has reach and seven toughness
However, many Field Spell cards have once per turn affects which can only be used by the player that controlls the card
Morbid really likes it when things line up a particular way, and it often relies on your opponents willingness to trade on your turn
Even so, tales of the Chaos Orb live on, including a myth of a player who, about to lose, shredded his Chaos Orb into pieces so it rained down on the opponents cards, destroying that players entire set-up (and theres a subsequent myth that the card-tearing player was ultimately disqualified since destroying the card resulted in a deck that with fewer than the required number of cards)
The issue with Teferi, Time Raveler is his mana cost makes him somewhat difficult to cast in a Dwarven Mine manabase