Time for some disordered cards:

Egoistic Suicide
Instant
Destroy target creature or planeswalker unless its controller controls another creature that shares a creature type with it.
For when one is not another, but an other.

Altruistic Suicide
Instant
Destroy target creature. Other creatures its controller controls get +1/+1 until end of turn.
A reason for living can become a reason for dying.

Anomic Suicide
Instant
Destroy target creature that became tapped or untapped this turn.
The world spins around all too quickly, and it's easy to find one's self nowhere.

Fatalistic Suicide
Instant
Cast ~ only during an opponent's second main phase.
Destroy target untapped creature that didn't enter the battlefield this turn. Its controller loses 1 life.
When there's nowhere to go, there's only one place to go.

Psychosis
Sorcery
Exile all cards from target opponent's hand, then they reveal all cards they own from outside them game. You choose one of those cards for each card exiled this way, then that player puts those cards into their hand.
Am I truly mad, or do I only think I am on account of my madness?

Aqueous Morphling
Creature - Weird
~ enters the battlefield with 4 tide counters on it, and gets +1/-1 for each tide counter on it.
: Choose one: put a tide counter on ~, or remove a tide counter from ~.
0/8

Goblin Detective
Creature - Goblin Advisor
Tapped creatures you control have vigilance.
: Target creature an opponent controls loses shroud and hexproof until end of turn.
1/1

Puck, Faerie Dragon
Legendary Creature - Dragon Faerie
Flying, Flash
If ~ entered the battlefield this turn, your opponents can't cast noncreature spells, and creatures your opponents control have no abilities.
2/2

Izzet Repurposer
Creature - Goblin Wizard
, discard a card: choose one --
-Draw a card
-~ deals 1 damage to target creature or player.
2/2
She turns old junk into more useful things -- like explosions.

Selesnya Channeler
Creature - Elf Druid
When ~ enters the battlefield, target creature gets +1/+1 until end of turn for each color among creatures you control.
2/2

Scarseer
Creature - Wraith Wizard
When ~ enters the battlefield, put a -1/-1 counter on target creature.
1/2

Conjurer's Mishap
Instant
Counter target creature spell. ~ deals damage equal to that spell's power to each creature.
Oops.

Prepared Response
Instant
Counter target spell if you've drawn a card this turn.

Cato these are really great! I especially like Universal Charm and Arrogant Duelist on the last page

Thanks, it's always nice to get feedback. I was pretty happy with how the charms turned out, but I couldn't think of good white or black ones.

Making some commons

Aquilor
Creature - Elemental
Whenever ~ attacks, it gets +1/-2 until end of turn.
1/3
"Water can drip and it can crash. Become like water my friend."
-Bruce Lee

Goblin Biker
Creature - Goblin Soldier
When ~ enters the battlefield, you may have another target creature gain first strike and haste until end of turn.
2/1

Berserker's Blood
Instant
Target creature gets +2/-2 until end of turn. Regenerate it.

Sorcerer of the Isles
Creature - Human Wizard
Prowess
2/3

Funsummon
Instant
Choose one:
-Return target creature to its owner's hand
-Draw a card

Rampaging Ogres
Creature - Ogre Barbarian
~ attacks each turn if able unless you pay
3/3
You can't spell "progress" without "ogres".

Primal Surge
Instant
Target creature gets +3/+3 and loses all abilities until end of turn.

More commons

Undertow
Sorcery
Put target creature on top of its owner's library. If was spent to cast ~, put that creature on the bottom of its owner's library instead.

Benalish Cadet
Creature - Human Soldier
When ~ enters the battlefield, choose one --
-Put a +1/+1 counter on ~
-Put a 1/1 white soldier creature token onto the battlefield.
1/1

Burnout
Instant
~ deals 3 damage to target creature or player. If that creature or player was dealt damage this turn, ~ deals 4 damage to it instead.

Entrail Reading
Sorcery
Destroy target creature, then scry x, where x is that creature's power.
"Everyone has a story inside of them, but some are better authors than others."
-Oszar, citadel counsel

Twiddel
Instant
Counter target spell. Tap or untap target permanent.

Blazing Blade
Instant
Target creature gets +2/+0 and gains first strike and trample until end of turn.

Ageless Aristocrat
Creature - Vampire
Sacrifice a creature: regenerate ~.
4/2

Imprison
Enchantment - Aura
Enchant creature
~ costs less to cast if it targets a tapped creature.
Enchanted creature can't attack or block, and its activated abilities can't be activated.

Shielding Light
Instant
Target creature you control gets +1/+2 until end of turn. You may return that creature to its owner's hand.

Greenhouse Keeper
Creature - Human Druid
, tap another untapped creature you control: Add one mana of any color to your mana pool.
2/2

Appropriate
Sorcery
Gain control of target creature until end of turn. Untap that creature. It gains haste and menace until end of turn.

Reflection
Sorcery
For each creature target opponent controls, put a token onto the battlefield that is a copy of that creature. Those tokens gain haste until end of turn. Exile them at the beginning of the next end step.

Undertow has some nice flavor and Appropriate is the type of card that begs for amazing art. I like them.

Not to be picky, but the name Primal Surge is already taken by a real card. Calling it Primal Strength may be good though.

I think I'll keep Reflection as is. It will occasionally be a drawback, but occasional drawbacks make the game more deep and interesting. Good catch on the primal surge.

I'm trying to make a core set. I think I'll fill out blue commons first:

Spell-Scale Drake
Creature - Drake
Flying
~ gets +0/+1 for each instant and sorcery card in your graveyard.
2/2

Seacoast Drake Reprint

Sorcerer's Familiar
Creature - Cat
Whenever you cast a noncreature spell, ~ gets +0/+2 and gains hexproof until end of turn.
2/1
Master Pellium always referred to him as 'her best apprentice', much to the chagrin of her pupils.

Rune-Shell Tortoise
Creature - Turtle
Sacrifice ~: Scry 2, then draw a card. Activate this ability only when you could cast a sorcery.
1/4

Meticulous Study
Sorcery
Draw a card.
Rebound

Catnap
Enchantment - Aura
Enchant Creature
Enchanted creature doesn't untap during its controller's untap step
Whenever you cast a noncreature spell, if enchanted creature is untapped, tap it.

Frost Breath reprint

Spellbound Serpent
Creature - Serpent
~ can't attack unless you've cast a noncreature spell this turn.
5/6

And some returning cards of mine:
Select
Funsummon and twiddel from above
Sorcerer of the isles from above is back, but it's 3/2 prowess this time.

And green:

Packmate Baloth
Creature - Beast
When ~ enters the battlefield, draw a card if you control another creature with power 4 or greater.
4/4

Crushing Vines reprint

Darkwood Basilisk
Creature - Beast
Deathtouch
3/3

Display of Dominance
Sorcery
Target creature you control gets +x/+x until end of turn, where x is the number of creatures you control, then fights target creature.

Darkwood Panther
Creature - Cat
Trample, Hexproof
3/1

Spiderling
Creature - Spider
Reach
Whenever an opponent casts a noncreature spell, ~ gets +1/+1 until end of turn.
1/3

Centaur Courser reprint

Avatar of the Forest
Creature - Treefolk
~ enters the battlefield with a +1/+1 counter on it for each other creature you control
3/3

Feral Invocation reprint

Evolution Charm reprint

And bringing back
Greenhouse Keeper (above)
Primal Surge (above), but renamed Primal Strength

And black:

Corpse-Cart Ox
Creature - Ox
When ~ enters the battlefield, you may put a creature card from a graveyard on top of its owner's library.
2/4

Runeshell Scarab
Creature - Insect
When ~ dies, scry 2.
2/1

Citadel Crow
Creature - Bird
Flying
Whenever a creature dies, ~ gets +1/+1 until end of turn.
2/1

Massive Ghoul
Creature - Zombie
Menace
5/3

Mindscar
Sorcery
Target player discards 2 cards. If that player had fewer than two cards in hand, they lose 2 life.
"Oszar has put a lot of thought into making sure no one else can."
-Pellium, archmagus of the isles

Citadel Rats
Creature - Rat
: ~ gains deathtouch until end of turn.
1/2

Offering to Vogol
Instant
Target player sacrifices a creature. If they do, they draw two cards.

Mark of the Vampire reprint

Scarseer, berserker's blood, ageless aristocrat, and entrail reading from above

Red:

Dragon Fodder reprint

Bolt of Thunder
Instant
~ deals 4 damage to target creature or player. Creatures dealt damage this way can't be regenerated this turn.

Fleeting Inspiration
Instant
Exile the top card of your library. Until end of turn, you may play that card.
Rebound

Ember Shaman
Creature - Goblin Shaman
At the beginning of combat on your turn, target creature gains menace until end of turn.
2/2

Forge Elemental
Creature - Elemental
When ~ dies, destroy target artifact.
3/2

Stormcaller Initiate
Creature - Human Shaman
Prowess
2/1

Stormcaller Adept
Creature - Giant Shaman
Prowess
3/3

Walking Sun
Creature - Elemental
When ~ enters the battlefield, it deals 1 damage to target creature. That creature can't block this turn.
4/3

Stone Rain
Shock reprint

Blazing Blade and Appropriate from above

I deleted my comment on Reflection in my post when I remembered the almost similar Clone Legion exists and is fine with things. I thought I deleted it quickly enough before you could read it. Even so, I am glad that poor comment had no effect on the card's design.

No problem. If I had a dollar for every stupid post I made, I'd have 5,606 dollars.

Now, moving on to white...

Cohort Griffin
Creature - Griffin
Flying
~ can't attack alone.
3/3

Cumulonimbus
Creature - Elemental
Flying
Whenever ~ attacks, you may have another target creature gain flying until end of turn.
1/1

Sword and Shield
Instant
Target creature gets +2/+0 and gains protection from the color of your choice until end of turn.

Inspired Charge reprint

Flashcifism
Enchantment - Aura
Enchant Creature
Flash
When ~ enters the battlefield, remove enchanted creature from combat.
Enchanted creature can't attack or block.

Purity of Will
Enchantment - Aura
Enchanted creature gets +2/+3

Koala
Creature - Koala
Sacrifice Koala: Destroy target enchantment.
2/2

Shadow Hunter
Creature - Human Wizard
, : Tap target creature.
2/2

Pillarfield Alpha
Creature - Ox
2/5
Its enemies are both oxidized and reduced.

Seller of Songbirds reprint

Smite the Monstrous reprint

Siegemaster of Dawn
Creature - Giant Soldier
Whenever ~ attacks or blocks, you may have another target creature get +1/+1 until end of turn.
3/5

And common artifacts:

Leonin Scimitar reprint

Spectum Stone
Artifact
: Add one mana of any color to your mana pool.

And common lands:
Evolving Wilds reprint
Shimmering Grotto reprint

Blue Commons:
Too much toughness, not enough power. Blue feels too defensive. Especially witohut quality fliers ot take advantage of ground stalls
Spell-Scale drake should either have flying or a better creature type.
Deny seems solid, but needs to specify what kind of ability, can it counter trample? Trample is an ability.
I dislike Twiddel because it gives your opponent to much power over the Twiddling, is Cancel a fine card? Yes. Is this strictly better? Yes, but it still feels bad, it has the feelbad trinket text problem.

Green Commons:
I'm concerned that nothing else at common rumbles with Molting Wurm, and Removal is bad against it. If the format was so aggressive that a 4/4 for 5 was too slow it might not be a problem, but I am not getting that at all. Maybe I like green too much in limited, but this feels like it is pushing the envelope at common.
You have too many creatures concentrated in the stat range, all of Green's creatures fall between 2/2 and 4/4, which a bunch around 3 toughness in particular. It makes all the green creatures feel replaceable.
Bear Familiar also has a mostly irrelevant ability that makes an otherwise solid card feel worse. It isn't like you are generally worried about losing your two drop to combat tricks anyways. If it got a +1/+1 counter it would probably be more interesting, but might push it towards uncommon.

Does your set not have any themes or keyword mechanics? Because I haven't noticed anything really, and they should really be apparent by this point. Even core sets had returning mechanics, this feels super vanilla.

Black Commons:
I think this should definitely be optional, commons shouldn't have feel bad modes on them in general. I'm not a huge fan of a common being used to lock up your opponent's drawstep either, but it is probably passable.
Citadel Crow's death boost is super weak, creatures just don't die pre-combat damage enough, I think I remember this effect being at common and giving +1/+1 counters before, which seem better.
It feels like black has a lot of cards that like sacrificing your stuff, and no cards that you want to sacrifice, which feels like a poor place to be for a theme.

Red Commons:
Red feels like it would have a hard time getting any of its creatures through, All the other colors of plenty of early drops, and red doesn't have any evasion to speak of, or first strike, or haste, or anything. It has the best removal, but that is about it.

White Commons:
I'm not a huge fan of a 4 drop that can't attack alone, it just feels bad to have my curve toppers not break board stalls.
Cumulonimbus is just really bad. It is basically Jump with Summoning Sickness.
White's combat tricks are both super good, one just wins combat, and the other makes attacking into white really hard. I would probably only have one or the other. White also getting a tapper, premium removal, and two massive meatshields of blockers makes me feel that white is the strongest color by far.

I don't feel like these commons really give a broad enough limited experience to make each of my drafts feel unique, I don't want my UG draft deck to feel like my BW draft deck, and all of these cards are clumped together in a way that makes board stalls feel inevitable nad matches to feel similar.

Oh, drake was supposed to have flying I just forgot to put it on the card. Nice catch.
Good catch on deny. I'll word it like Stifle
I think I'll keep it as is. The trinket text can randomly let you get an extra spell off by untapping a land, so it will be relevant sometimes.

Wurm: I think it's safe. Basilisk, rats, shadow hunter, walking sun, siegemaster, massive ghoul, spellbound serpent, pillarfield alpha, ageless aristocrat, and avatar of the forest can all deal with it.
Green creatures being generic and replaceable: fair point. I'll try to vary up the creatures somewhat.
Bear Familiar: I mostly had that in there as a sort of mirror to prowess. And I think the ability will come up more often than you realize: remember, blue and red will want to cast their spells before or during combat for the triggers.

Themes and mechanics: UR has spells, b/r has dragon fodder and appropriate + sac outlets, RW has aggro, green has generic green durdliness and also some fixing so you can build multicolor decks around higher rarity cards. White does feel kinda generic though.

Black: You're supposed to pair it with red for the good sac fodder.
Crow is a 2/1 flier for . Those have been printed before without any upside, and I think there is real upside. You can use removal precombat to get an extra point of damage in, use threat of activation to bluff your way past seacoast drake, or just sac your whole team to aristocrat to finish them off.

Red: Yeah, you're probably right about that. I think the best way to redress that imbalance is to change other colors, so that red matches up against them better.

Griffin: I think it's fine. A 3/3 flier is ahead of the curve, you can run it with other fliers, and if worst comes to worst, you can always suicide in your other guys to force damage through.
Cumulonimbus: Damn, that was supposed to have flying too. I need to proofread my cards better.
White tricks: Yeah, I didn't want to make valorous charge, but I ran out of design space before I had enough commons. I'll try to think of something else.

Changes:
-Added flying to Cumulonimbus and Spell-Scale Drake
-Updated wording on deny
-Cut benalish cadet for Yoked Ox reprint. It enables the "attacking together" theme, gives white more control potential, and reduces the number of 2/2s for 2 in the set.

Replaced Valorous Charge with Inspired Charge reprint.

-Cut Bear Familiar for
Spiderling
Creature - Spider
Reach
Whenever an opponent casts a noncreature spell, ~ gets +1/+1 until end of turn.
1/3
Reduces number of bears in set further, diversifies creatures, and doesn't belong in every green deck.

Cut Darkwood Spinner for:
Darkwood Panther
Creature - Cat
Trample, Hexproof
3/1
Synergy with pump spells and auras, but bad enough as vanilla that most decks don't want it.

Black:
Replaced Black Bear with:
Runeshell Scarab
Creature - Insect
When ~ dies, scry 2.
2/1

Replaced Twisted Cycle with:
Mindscar
Sorcery
Target player discards 2 cards. If that player had 2 or fewer cards in hand, they lose 2 life.

Blue:
Edited Runeshell Tortoise to scry 2 before drawing.

Thanks for the feedback. I know I didn't agree with everything you said, but I fixed the wording errors, and tried to take your suggestions into account, diversifying the creatures to try to make decks more specialized.

A cycle of uncommon thematic enablers:

Garrison Lieutenant
Creature - Human Soldier
Whenever you attack or block with 3 or more creatures, put a 2/2 white knight creature token onto the battlefield.
3/3

Master of the Isles
Creature - Human Wizard
Whenever you draw a card, if it isn't your draw step, you may return target creature to its owner's hand.
3/3

Stormcaller Journeyman
Creature - Ogre Shaman
Whenever a source you control deals noncombat damage, creatures you control get +1/+0 and gain first strike until end of turn.
3/3

Citadel Overseer
Creature - Human Advisor
Whenever a player sacrifices a creature, or a creature is destroyed by a spell or ability you control, you may pay 1 life. If you do, draw a card.
3/3

Darkwood Beastmaster
Creature - Human Warrior
At the beginning of your upkeep, put 2 +1/+1 counters on target creature if you control a creature with power 4 or greater.
3/3

No problem, I'm just giving a fresh look, limited development is mostly playtesting, which is of course incredibly difficult.

Master of Isles: It is called your draw step

Citadel Overseer: This feels suspiciously powerful in constructed, but I might be missing a good reference.