More technically, copy effects only use the attributes of the object at the time it's copied, not the full card representing the object
Before we get too deep into all this info, lets take a look at the lands in question, shall we
Victor, Valgavoths Seneschal Victor, Valgavoth's Seneschal is bonkers in Yorion, Sky Nomad decks where you get to blink a lot of enchantments at once
Getting to draw cards and create Treasures is great, but not at the expense of losing this creature that you already spent your mana on
Cards like Impulse are never the all-stars in a cube deck, but theyre good cards that tie the room together, by representing something to do when holding up counterspell magic
At the beginning of your upkeep, if you have 5 or less life, you may transform Arguels Blood Fast