So I was on a walk today, and was thinking about Magic, as I sometimes do. Today I was thinking of conditional spells. I love the balancing factor of casting a spell that's underpowered for its cost, but potentially more powerful in the right situation. The most common (especially in modern magic) are red burn spells. So I sought to create a flavorful representation of a spell that improves under certain circumstances. I settled on a red burn spell. But what condition to meet? Damage dealt of course. So I came up with this card:
Sulfur Burn
Instant
~ deals 2 damage to target creature or player. If that creature or player has been dealt damage this turn, ~ deals 4 damage instead.

Marginally worse than Lightning Bolt but sometimes better. But what if I expanded this? The next color I considered was blue. What does blue want to do? Either card draw or mill (putting cards from libraries to graveyards). So I came up with these three options:
1. Mind Block
Sorcery (Design note: This was originally an instant, but instant speed mill is pretty weak)
Target player puts the top three cards of their library into their graveyard. If that player has had a card put into their graveyard from their library this turn, that player puts the top ten cards instead.
(Design note: This feels really wordy to me. Plus it only works well as a sorcery, and I prefer cycles to be the same card type, when possible. Sulfur Blast really works as either, though I would probably up the damage to 3 and 5 respectively.)
2. Thought Cascade
Sorcery
Draw a card. If you haven't drawn a card this turn, draw three instead.
(Design note: This one feels to specific. It requires to much of a build-around.)
3. Thought Cascade
Sorcery
Draw a card. If you have drawn more than one card this turn, draw two instead.

Next I turned to black. Black generally runs discard or life loss. In this case, life loss seems too close to red. So discard was the way to go, which solidifies the cycle to sorcery speed.
Mindbore
Sorcery
Target player discards a card. If that player has discarded a card this turn, that player discards their hand instead.

Green and white present a challenge. Both could be life gain, though white is primary in that. Green usually does pump, but that could be too specific a condition.
Rush of Life
Sorcery
You gain 4 life. If you have gained life this turn, gain 10 life instead.

So any suggestions for the green effect?

Squirrel Herding
Instant
Put a 1/1 green Squirrel Creature token onto the battlefield. If another Creature has entered the battlefield under your control this turn, put three of those tokens onto the battlefield instead.

(I don't know, the basic effect is slightly stronger than the others. Maybe this would have to be a sorcery too?)

I like the effect and I think there is a ton of design space. I would Ability word it, like Resonance, Reflect, (cascade and/or ripple would have been nice), Chain, Boon, Boost, Build, Crest, Fate, Destiny, bah I don't know.

Frito Slays
Instant
Destroy target creature.
Destiny - If you destroyed another creature this turn, destroy target creature.
Betcha can't kill just one.

Awful jokes aside, that one is a lot like Morbid, but there is literally a sets worth of ideas there.

How long did you contemplate the power level of this card?

Part of me find the interactions with the cards less interesting because they reward you for doing what you wanted to do anyway.

Well, if you don't have a prior discard spell, this is below par. Further into the game, it becomes better, but also worse, because generally they have played more of their hand. I suppose making it if that player has discarded two cards.

@ Aaarrgh: SQUIRELLS! I wish they would re-introduce squirells...

@Dudibus: I think it has quite a bit of potential. The hard thing is balancing the lesser and greater effects to average at the mana cost. And of course the more hoops you have to jump through, the stronger it can be.

Would be interesting to see an opposite style burn spell:
Target player takes 3 damage. If that palyer has gained life this turn, that player takes 5 damage instead.

T1: Swamp, Dark Ritual, 1/2 CMC Discard, Mindbore

Even without Dark Ritual, it can very easily leave someone without a hand by turn 2 as it is now.

yeah it's "overpowered"

Is this sarcasm?

no your card is insanely powerful

I would say for each of those cards, the correct mana cost should be inbetween what you would normally expect to pay for each of those effects (put on the high side).

So for the first one, Sulfur Burn, the cost should be or , as that's between Shock and Lightning Blast.

Same with the others. 1 mana to have them discard 1 card isn't much, but 1 mana to have them discard their hand is insane. What happens when you turn 2 on the play and cast 2 of these? That's a slap in the face. Instead, Mindbore should cost , as Cry of Contrition costs and Wit's End costs

Mindbore
Sorcery
Target player discards a card. If that player has discarded two or more cards this turn, that player discards their hand instead.

Generally, discarding 2 cards can't be done for less than 3 mana, unless your casting two cheaper discard spells. Thus, in order to pull this off, you will have to be third turn+, with the exception of Dark Ritual, which is only legal in vintage/legacy anmd edh.

I would make it this

Mindbore |
Sorcery
Target player discards a card. If that player has discarded a card this turn, they discard two cards instead.

so it's slightly better than mind rot if you meet the condition

I was kinda going for 1 mana across the cycle.

How about:
Mindbore (P.S. Why isn't there a card called mindbore?)
Sorcery
Target player discards a card. If that player has discarded one or more cards this turn, that player discards that many cards instead.

Actually I kind of like that scaling effect... but its so strong when combo'd. Granted with discard its not as strong, because there's only so much for them to discard.

It's actually kinda weak now since you have to have made the opponent discard twice before for it to do any more than 1.

Though I guess 3 damage to the face and 4 discard for 1RBB (Blightning) or discard 4 for BBB (Hymn to Tourach) is hardly bad.

sticking with one mana only means that you will end up with some cards, this one for example, that can't be balanced.

they either suck or are too good

I could up the cycle to cmc 2. But the others would probably need to powered up. I hate horizontal cycles that have that one oddball.