These will transform after you fulfill some kind of condition on the card, usually either an activated ability (i.e., paying to exile Terra, Magical Adept) or triggered ability (i.e., having six permanents in the yard for Exdeath, Void Warlock at end of turn)
While I think that seven mana is expensive to get something that does nothing on its own, you can always cast Fractured Realm first and then cast Mirror Room in order to make two Reflections for the price of one
Heres how you can grab each, whats included, and all the key info you need to help you decide whether you still want these to add to your collection via third party seller listings selling at a premium
Toralf, God of Fury ($3 to $6) This will be terribly fun with spells that deal more than one damage
I almost always manage to get two attackers down early
General Beatrix can help with equip costs later in the game