So here's the scenario, Lazav, Dimir Mastermind is on the field and I self mill a god like Phenax, God of Deception. So now Lazav is a copy of said god, great. The question being does Lazav need devotion to be a creature, or need a creature sacrifice to attack/block(Bontu the glorified), or need 7 cards to attack/block(Kefnet the mindful)? (I assume yes). Here's the source of my confusion, All the gods specifically say either "god's name" is not a creature unless you have X devotion, or "god's name" can't attack/block unless X condition is met. HOWEVER, unlike most clone effects Lazav specifically changes the name of the creature to Lazav, Dimir Mastermind.
Tldr: So in the end do you have a card that is
[1]
Lazav, Dimir Mastermind (3)(U)(B)
Indestructable Hexproof.
As long as your devotion to blue and black is less than seven, Phenax isn't a creature.
Creature you control have "(tap) target player puts the top X cards of his or her library into his or her graveyard, where X is this creature's toughness."
4/7
OR....
[2]
Lazav, Dimir Mastermind (3)(U)(B)
Indestructable Hexproof.
As long as your devotion to blue and black is less than seven, Lazav isn't a creature.
Creature you control have "(tap) target player puts the top X cards of his or her library into his or her graveyard, where X is this creature's toughness."
4/7
Quicksilver Elemental provides the context you need for your question - when a permanent copies an ability of another permanent, all instances of the second permanent's name in that ability get changed to the first permanent's name for intelligibility purposes. Lazav will not be a creature unless your devotion is sufficiently high.
Note, that Lazav only copies a creature card that enters your opponent's graveyard, so self milling a creature won't let him copy it.
In general, if a card refers to itself by name, like the Gods, that only means [this object]. If an ability wants to refer to the name specifically, it will use the phrase "card/creature/etc. named ...". For example, see Mirror-Mad Phantasm. The ability first references [this permanent], and later lets you "search" for a "card named Mirror-Mad Phanstasm".
Tldr: So in the end do you have a card that is
[1]
Lazav, Dimir Mastermind (3)(U)(B)
Indestructable Hexproof.
As long as your devotion to blue and black is less than seven, Phenax isn't a creature.
Creature you control have "(tap) target player puts the top X cards of his or her library into his or her graveyard, where X is this creature's toughness."
4/7
OR....
[2]
Lazav, Dimir Mastermind (3)(U)(B)
Indestructable Hexproof.
As long as your devotion to blue and black is less than seven, Lazav isn't a creature.
Creature you control have "(tap) target player puts the top X cards of his or her library into his or her graveyard, where X is this creature's toughness."
4/7
I̟̥͍̠ͅn̩͉̣͍̬͚ͅ ̬̬͖t̯̹̞̺͖͓̯̤h̘͍̬e͙̯͈̖̼̮ ̭̬f̺̲̲̪i͙͉̟̩̰r̪̝͚͈̝̥͍̝̲s̼̻͇̘̳͔ͅt̲̺̳̗̜̪̙ ̳̺̥̻͚̗ͅm̜̜̟̰͈͓͎͇o̝̖̮̝͇m̯̻̞̼̫̗͓̤e̩̯̬̮̩n͎̱̪̲̹͖t͇̖s̰̮ͅ,̤̲͙̻̭̻̯̹̰ ̖t̫̙̺̯͖͚̯ͅh͙̯̦̳̗̰̟e͖̪͉̼̯ ̪͕g̞̣͔a̗̦t̬̬͓͙̫̖̭̻e̩̻̯ ̜̖̦̖̤̭͙̬t̞̹̥̪͎͉ͅo͕͚͍͇̲͇͓̺ ̭̬͙͈̣̻t͈͍͙͓̫̖͙̩h̪̬̖̙e̗͈ ̗̬̟̞̺̤͉̯ͅa̦̯͚̙̜̮f͉͙̲̣̞̼t̪̤̞̣͚e̲͉̳̥r͇̪̙͚͓l̥̞̞͎̹̯̹ͅi͓̬f̮̥̬̞͈ͅe͎ ̟̩̤̳̠̯̩̯o̮̘̲p̟͚̣̞͉͓e͍̩̣n͔̼͕͚̜e̬̱d̼̘͎̖̹͍̮̠,͖̺̭̱̮ ̣̲͖̬̪̭̥a̪͚n̟̲̝̤̤̞̗d̘̱̗͇̮͕̳͕͔ ͖̞͉͎t̹̙͎h̰̱͉̗e̪̞̱̝̹̩ͅ ̠̱̩̭̦p̯̙e͓o̳͚̰̯̺̱̰͔̘p̬͎̱̣̼̩͇l̗̟̖͚̠e̱͉͔̱̦̬̟̙ ̖͚̪͔̼̦w̺̖̤̱e͖̗̻̦͓̖̘̜r̭̥e͔̹̫̱͕̦̰͕ ̗͔̠p̠̗͍͍̱̳̠r̰͔͎̰o͉̥͓̰͚̥s̟͚̹̱͔̣t͉̙̳̖͖̪̮r̥̘̥͙̹a͉̟̫̟̳̠̟̭t͈̜̰͈͎e̞̣̭̲̬ ͚̗̯̟͙i͍͖̰̘̦͖͉ṇ̮̻̯̦̲̩͍ ̦̮͚̫̤t͉͖̫͕ͅͅh͙̮̻̘̣̮̼e͕̺ ͙l͕̠͎̰̥i̲͓͉̲g̫̳̟͈͇̖h̠̦̖t͓̯͎̗ ̳̪̘̟̙̩̦o̫̲f̙͔̰̙̠ ̹̪̗͇̯t͖̼̼͉͖̬h̹͇̩e͚̖̺̤͉̹͕̪ ͚͓̭̝̺G͎̗̯̩o̫̯̮̟̮̳̘d̜̲͙̠-̩̳̯̲̗̜P̹̘̥͉̝h͍͈̗̖̝ͅa͍̗̮̼̗r̜̖͇̙̺a̭̺͔̞̳͈o̪̣͓̯̬͙̯̰̗h̖̦͈̥̯͔.͇̣̙̝
In general, if a card refers to itself by name, like the Gods, that only means [this object]. If an ability wants to refer to the name specifically, it will use the phrase "card/creature/etc. named ...". For example, see Mirror-Mad Phantasm. The ability first references [this permanent], and later lets you "search" for a "card named Mirror-Mad Phanstasm".
Former Rules Advisor
"Everything's better with pirates." - Lodge
(The Gamers: Dorkness Rising)
"Any sufficiently analyzed magic is indistinguishable from science."
(Girl Genius - Fairy Tale Theater Break - Cinderella, end of volume 8)