So, my current network hit 50 epochs. It's 3-layer, with rnn_size = 300 and dropout = .25. It still generates an annoyingly high amount of cards that just don't work, but it makes some interesting stuff too. Here's some examples of what I'm getting at temperature = .7:
fury sledge 4
artifact creature ~ spirit
whenever @ attacks, defending player sacrifices a creature.
2/2
#Hmm... interesting, but probably belongs in black. Also, as you'll see, my network is really bad at mana costs.
firebrand 6GG
creature ~ beast G: regenerate @.
7/7
#A big green beast with regenerate? Nice and on-color.
cylian caves
land T: add 1 to your mana pool. 1, T, sacrifice @: search your library for a basic land card, reveal it, and put it into your hand. if you do, shuffle your library.
when @ is put into a graveyard from the battlefield, if it was kicked, it enters the battlefield with four -1/-1 counters on it. 1BB, remove a +1/+1 counter from @: target creature gets +2/+2 until end of turn.
#This looked like it was going to work... then... I don't even know what happened.
swipe in uberant 1U
enchantment ~ aura
enchant creature
whenever enchanted creature deals combat damage to a player, put a +1/+1 counter on each other creature that shares a creature type with that creature instead.
#The wording seems off, and it probably doesn't belong in blue, but I like this concept.
surging trought 4
artifact 6, T: target creature gains flying until end of turn.
#In the glorious tradition of Jump...
croqual dromoka 4W
creature ~ kithkin soldier
vigilance
at the beginning of each end step, if you control a blue or blue permanent you control, @ gets +2/+2 until end of turn.
2/4
#Blue or blue, nothing else will do.
archangel of the turns 1R
creature ~ human soldier
first strike, haste
whenever a player casts a blue spell, you may pay B. if you do, put X 3/3 green wolf creature tokens onto the battlefield, where X is the number of % counters on it.
#Alright, the card as a whole doesn't really work, but I'm happy that the network made a card that used X properly.
Well, I just gave X casting cost cards a go with my epoch 26 checkpoint. No luck at temperature = .7. Out of roughly 40 cards (5000 characters) generated at a temperature of .4, I only managed to find 2 that had a second X:
planeswalker's phantasm X
creature ~ elemental
@ enters the battlefield with X +1/+1 counters on it. 3, T, remove a % counter from @: put a 1/1 green saproling creature token onto the battlefield.
10/10
fallen research X
sorcery
@ deals X damage to target creature or player.
So, using the resources posted by Talcos and hardcast, I set up a network that I can prime with anything I want. Everything seems to be coming along nicely at 22 epochs, except one thing: Planeswalkers. All of the Planeswalkers I've generated have had only one proper ability each. The ability is always one that adds loyalty, generally +1. No matter what I do, it won't generate one with more than one ability. Is this a common problem, or is the issue with my network in particular?
This is really fascinating stuff. I signed up for an account on this site solely because of this thread!
I set up a network of my own, but I didn't mess with the settings too much. Here's some early results that I found interesting (for various reasons...)
Brice of the Wall 2
Artifact 4, T: $THIS dies for its flashback cost.)
$THIS enters the battlefield under another creature spell.
#It lurks under a creature spell... then when your opponent least expects it... you make it die for its flashback cost!
Goblin Excants (W/B)(W/U)
Creature Goblin Warrior
At the beginning of your upkeep, put an age counter on this permanent, you choose a noncreature spell this turn, you may pay 1BG and have "W: This creature enters the battlefield under your control, $THIS gains first strike until end of turn.
3/2
#Only color missing from this one is red. Also, random age counters FTW!
Anacour the Dragon 3U
Creature Elemental
When $THIS enters the battlefield, if it was sep, target artifact or player this turn.
4/3
#I'd run four in my sep deck.
Kobol 5B
Creature Merfolk
When $THIS dies, you may pay 1. If you do, put a 2/2 green Wolf creature token with flying onto the battlefield. T: Add 1 to your mana pool. 1, T: Until end of turn, creatures you control have haste as long as you control four land you divide that creature's commated for its base power and toughness are each equal to the number of cards in the chosen type get +1/+1 and hand is red can't be blocked except by two or more creatures this turn.
3/2
#The first two abilities are way off-color (and yay for flying wolves!), but make sense. That third one, though...
Seart to Varako BBB
Creature Goblin Warrior Mer
Whenever $THIS deals combat damage to a creature, put it onto the battlefield. Then shuffle your library.
2/3
#Wait, isn't it already on the battlefield if it's dealing damage? Also, it appears my network also likes library shuffling.
Ankane Knight GG
Instant Arcane
Convoke (Your creatures can help cast bester the battlefield.
#It doesn't appear to actually do anything, but hey, your creatures can help cast bester!
Heards of Alasmint 2R
Creature Ogre Warrior T: Return target creature cards from your graveyard to your hand.
Evoke 2R (You may cast this card face down as a 2/2 creature for 3. Turn it from another whise lef.
2/2
#wat
Expire Regent 1G
Creature Elf Shaman 1W: $THIS gets +2/+2 until end of turn.
1/2
#A bit odd that it pumps with white, but at least it's coherent.
Reptrate 5RR
Instant
$THIS deals 1 damage to target creature or player this turn.
#Wording's a bit funny, and this might be just a bit overcosted...
Rensence W
Legendary Creature Human Soldier G, T: Add 1 to your mana pool.
1/2
#The network's first stab at a Legendary. Unfortunately, it sucks.
Centroos 2UU
Sorcery
Exile target creature card from your hand.
#I had quite a run of terrible cards.
Rootnight 4B
Creature Human Samurai
When $THIS enters the battlefield, tap target creature. That creature gets +1/+1 until end of turn.
3/2
#Overcosted and likely off-color, but the ability is pretty interesting.
Kore Balloon 3R
Instant
Destroy target creature.
#Somewhat overcosted red removal. Probably off-color, again, but not bad.
Braulet Dream 1W
Instant
Destroy all creatures. They can't be regenerated.
#Because Wrath of God wasn't good enough.
4
artifact creature ~ spirit
whenever @ attacks, defending player sacrifices a creature.
2/2
#Hmm... interesting, but probably belongs in black. Also, as you'll see, my network is really bad at mana costs.
firebrand
6GG
creature ~ beast
G: regenerate @.
7/7
#A big green beast with regenerate? Nice and on-color.
cylian caves
land
T: add 1 to your mana pool.
1, T, sacrifice @: search your library for a basic land card, reveal it, and put it into your hand. if you do, shuffle your library.
when @ is put into a graveyard from the battlefield, if it was kicked, it enters the battlefield with four -1/-1 counters on it.
1BB, remove a +1/+1 counter from @: target creature gets +2/+2 until end of turn.
#This looked like it was going to work... then... I don't even know what happened.
swipe in uberant
1U
enchantment ~ aura
enchant creature
whenever enchanted creature deals combat damage to a player, put a +1/+1 counter on each other creature that shares a creature type with that creature instead.
#The wording seems off, and it probably doesn't belong in blue, but I like this concept.
surging trought
4
artifact
6, T: target creature gains flying until end of turn.
#In the glorious tradition of Jump...
croqual dromoka
4W
creature ~ kithkin soldier
vigilance
at the beginning of each end step, if you control a blue or blue permanent you control, @ gets +2/+2 until end of turn.
2/4
#Blue or blue, nothing else will do.
archangel of the turns
1R
creature ~ human soldier
first strike, haste
whenever a player casts a blue spell, you may pay B. if you do, put X 3/3 green wolf creature tokens onto the battlefield, where X is the number of % counters on it.
#Alright, the card as a whole doesn't really work, but I'm happy that the network made a card that used X properly.
planeswalker's phantasm
X
creature ~ elemental
@ enters the battlefield with X +1/+1 counters on it.
3, T, remove a % counter from @: put a 1/1 green saproling creature token onto the battlefield.
10/10
fallen research
X
sorcery
@ deals X damage to target creature or player.
I set up a network of my own, but I didn't mess with the settings too much. Here's some early results that I found interesting (for various reasons...)
Artifact
4,
T: $THIS dies for its flashback cost.)
$THIS enters the battlefield under another creature spell.
#It lurks under a creature spell... then when your opponent least expects it... you make it die for its flashback cost!
Goblin Excants (W/B)(W/U)
Creature Goblin Warrior
At the beginning of your upkeep, put an age counter on this permanent, you choose a noncreature spell this turn, you may pay 1BG and have "W: This creature enters the battlefield under your control, $THIS gains first strike until end of turn.
3/2
#Only color missing from this one is red. Also, random age counters FTW!
Anacour the Dragon 3U
Creature Elemental
When $THIS enters the battlefield, if it was sep, target artifact or player this turn.
4/3
#I'd run four in my sep deck.
Kobol 5B
Creature Merfolk
When $THIS dies, you may pay 1. If you do, put a 2/2 green Wolf creature token with flying onto the battlefield.
T: Add 1 to your mana pool.
1, T: Until end of turn, creatures you control have haste as long as you control four land you divide that creature's commated for its base power and toughness are each equal to the number of cards in the chosen type get +1/+1 and hand is red can't be blocked except by two or more creatures this turn.
3/2
#The first two abilities are way off-color (and yay for flying wolves!), but make sense. That third one, though...
Seart to Varako BBB
Creature Goblin Warrior Mer
Whenever $THIS deals combat damage to a creature, put it onto the battlefield. Then shuffle your library.
2/3
#Wait, isn't it already on the battlefield if it's dealing damage? Also, it appears my network also likes library shuffling.
Ankane Knight GG
Instant Arcane
Convoke (Your creatures can help cast bester the battlefield.
#It doesn't appear to actually do anything, but hey, your creatures can help cast bester!
Heards of Alasmint 2R
Creature Ogre Warrior
T: Return target creature cards from your graveyard to your hand.
Evoke 2R (You may cast this card face down as a 2/2 creature for 3. Turn it from another whise lef.
2/2
#wat
Creature Elf Shaman
1W: $THIS gets +2/+2 until end of turn.
1/2
#A bit odd that it pumps with white, but at least it's coherent.
Reptrate 5RR
Instant
$THIS deals 1 damage to target creature or player this turn.
#Wording's a bit funny, and this might be just a bit overcosted...
Rensence W
Legendary Creature Human Soldier
G, T: Add 1 to your mana pool.
1/2
#The network's first stab at a Legendary. Unfortunately, it sucks.
Centroos 2UU
Sorcery
Exile target creature card from your hand.
#I had quite a run of terrible cards.
Rootnight 4B
Creature Human Samurai
When $THIS enters the battlefield, tap target creature. That creature gets +1/+1 until end of turn.
3/2
#Overcosted and likely off-color, but the ability is pretty interesting.
Kore Balloon 3R
Instant
Destroy target creature.
#Somewhat overcosted red removal. Probably off-color, again, but not bad.
Braulet Dream 1W
Instant
Destroy all creatures. They can't be regenerated.
#Because Wrath of God wasn't good enough.