Welcome to part 3 of the custom card set tutorial. In this part I'll right about making the cards in the set follow the lore.
Lore to Gameplay
To make custom mechanics, you need to take the colors of the faction and make 1-3 themes, based on how many colors it has. Each color has different themes that change based on how they mix. Here is the reference. You may warp it, this is just based Magic reference. Some colors have overlaps. These are themes you might want for factions of those colors
White: Soldiers, survival, peace, brotherhood, life gain, spirits, damage block, angels, destroy monsters, giants, protection during your turn, tokens, enchantments, exile, return to battlefield/from graveyard, exile enchantments, the law, armies
Blue: Card draw, scry, krakens and sea life, merfolk, drakes, wizards, enchantments, control, sphinx, clones, confusion, counters, mill, spirits, cunning, elementals, tapping, ice, water, air, the law
Black: Death, zombies, skeletons, spirits, vampires, assorted other undead, destroy, discard, mill, life loss, life gain, sacrificing, return to battlefield/from graveyard, gorgons, search library
Red: Orcs, goblins, ogres, giants, aggression, war, speed, dragons, fire, lightning, damage, vampires, elementals, angels, destroy artifacts, ramp, armies
Green: Nature, strength, monsters, beasts, animals, destroy artifacts or enchantments, elves, elementals, ents, snakes, spiders, scorpions, gorgon, the hunt, search library, regeneration, ramp, growth,
There are many more, these are just a few of the ones that I could think of. Make sure that the themes fit the lore for each faction, as well as the ability you make not stray to far from it as well. In your story, if someone from a faction shows the hero how to breath underwater, don't forget to have something in the ability that makes that part of the story make sense.
Now that you have your themes, make mechanics based off of them. If its white/black and you choose spirits and life gain, make an ability that is a weaker lifelink with a weaken creature's spirit bonus or something (#Draining from Forgotten Dragons). Encompass both of them into the ability, without making both too obvious. Once you get all five custom faction only mechanics, choose 2-3 other NOT EVERGREEN abilities to include as well with all of the evergreen. These abilities may be used by any faction, like Morph in Khans, and Kicker in other sets.
This is probably the most important step. Setting up the count. In order to do this, you need to say how many cards you want in the set. Then you want to split it up into commons, uncommons, rares and mythics. Under each of the categories, right each color and then each of the multicolor combos you are using. If you are making a three color set, you should have closer to 400 cards, when 2 color wants 350 and 1 color wants 300. Underneath that, right a count for creatures, legendary creatures, instants... and so on. Also write any cycles below that. Remember to make the count super detailed and clear. If the count every gets wrong. Cease production on cards until it's fixed.
A 400 card set should have 200 commons; 140 uncommons, 45 rares, and 15 mythics. This can be changed, but the proportions should stay similar
Here is the count for Forgotten Dragons as an example:
CARD COUNT (136/330)
W/B: 5/5 (1 Regent; 1 Command; 1/1 Khan; 2/2 Other)
W/R: 3/5 (1 Regent; 1 Command; 1/1 Khan; 1/2 Other)
G/U: 3/5 (1 Regent; 0 Command; 1/1 Khan; 2/2 Other)
B/G: 3/5 (1 Regent; 0 Command; 1/1 Khan; 1/2 Other)
U/R: 2/5 (1 Regent; 0 Command; 1/1 Khan; 0/2 Other)
G/U: 1/1 (Planeswalker)
R/W: 0/1 (Planeswalker)
W/B: 1/1 (Dragonlord)
W/R: 1/1 (Dragonlord)
G/U: 1/1 (Dragonlord)
B/G: 1/1 (Dragonlord)
U/R: 1/1 (Dragonlord)
Legendary Creatures 10/10
Kilastar - 30/65
Memaphite - 27/65
Nosai - 33/65
Pastika - 20/65
Ryduter - 26/65
Instant => Dragon Auras: 3/5
Rare Megamorph: 1/5
Dragonlord Monuments: 0/5
Dragon's Lands 5/5
Colorless Artifact Equipments: 2/5
Mono Colored Artifacts: 0/5
Clan Hatchlings: 5/5
_scale Sweeper: 3/5
Designing Commons and Uncommons
When you first start making cards, don't make fillers yet. You want to take the story, and make a card for every detail, every person they meet, every spell cast on them. If they meet barbarians in the mountains, add those Hardened Barbarians as a creature. If they get thrown in a box and buried alive, make Claustrophobia. You also don't want to make remakes except for filler cards. These cards mean something to the story. Once those are all out of the way, you can make fillers. Make troops, and animals, make remakes only when you are 3/4< ways towards done with the commons and uncommons. Remember the rares and mythics define the set. The commons and uncommons make the set. Sets would be nothing without them.
Making commons doesn't need that much help, since they don't need that much background after what was said in the paragraph above. But remember that each color should have a similar amount of each card type, based on its color. Blue should have a higher instant and sorcery count than green, and vise versa for creatures.
Sorry, but due to the amount of room, you must TUNE IN NEXT TIME TO LEARN ABOUT RARES, MYTHICS, AND CYCLES!!!