Here now are the red rare cards I've designed for my custom set.
Avalanche Herald 2RR
Creature - Elemental
Alpha - Whenever this creature becomes blocked, if its power is greater than or equal to the power of a creature blocking it, you may destroy target nonbasic land.
3/3
Avalaunch 1RR
Enchantment
Sacrifice a mountain: Put two 1/1 red Goblin creature tokens with haste onto the battlefield.
Bloodshed Arena 3RR
Enchantment
Whenever a creature with power 5 or greater enters the battlefield under your control, you may have that creature fight a creature target opponent controls.
Fodder Bomb RR
Sorcery
Destroy all Goblins.
Fodder Bomb deals X damage to target player, where X is equal to the number of Goblins destroyed this way.
Furywing Hellkite 3RR
Creature - Dragon
Flying
Madness 4RRR
When Furywing Hellkite enters the battlefield, if its madness cost was paid, other creatures you control get +X/+0 and gain haste until end of turn, where X is equal to Furywing Hellike's power.
5/5
Heterical Ceremony 2R
Enchantment
Whenever an opponent taps an artifact, that player sacrifices it unless they have Heterical Ceremony deal 2 damage to him or her.
Roaring Lavavore 1RR
Creature - Elemental
Trample, haste
Berserk 2RR (Whenever this creature attacks, you may pay 2RR. If you do, it gets +X/+0 until end of turn, where X is equal to its power. Sacrifice it at the beginning of the next end step.)
4/1
Wulgor Hellkite 5RR
Creature - Dragon
Flying
Cunning - When you cast Wulgor Hellkite, if you have five or more cards in your hand, it deals 5 damage among any number of target creatures.
5/5
Avalanche Herald is pretty strong for limited, but it's too simple to be a rare.
Avalaunch is Goblin Trenches in one color, with no activation cost, and the tokens have haste. Probably too strong.
Bloodshed Arena is Where Ancients Tread with a couple of downsides (can't hit players, can kill your creature), which is pretty bad, even if it can sometimes kill creatures with 6+ toughness.
Fodder Bomb is Goblin War Strike with a downside, unless you're playing against Goblins, in which case it's a really strong hoser.
Furywing Hellkite's ETB effect is a bit too good. It's pretty much "you win" if you have a couple of other creatures out. It's also pretty strong when hardcast.
Heretical Ceremony isn't very strong. It's almost strictly worse than Null Rod and worse than Stony Silence.
I think Roaring Lavacore is a bit too strong. 4 power and haste for 3 mana makes it one of Red's most efficient 3-drops ever.
Wulgor Hellkite has the same problem that Saviors of Kamigawa's Wisdom cards had: it forces you to not play cards. This is especially bad in Red, which is the color that's most likely to empty its hand. For one mana more, you could just play Bogardan Hellkite, which is better in multiple ways.
Avalanche Herald - it is repeatable land destruction though if it's swinging through.
Avalaunch - This could probably cost a bit more and have an activation cost.
Bloodshed Arena - It gets around hexproof and shroud.
Fodder Bomb - I was going for Goblin War Strike and Last Ditch Effort. Just something fun and funny.
Furywing - Maybe cost it one more? increase the madness cost? change the madness ability?
Heterical Ceremony - Maybe reduce the cost? Increase the damage?
Roaring Lavacore - Increase the cmc? increase the berserk cost?
Wulgor Hellkite - Cunning is all about when to play the cards you have in your hand. True, it forces you to keep several cards in hand, and red is very impatient. Maybe reduce the cost by a bit? 1 or 2 at the most?
Bloodshed Arena - Indeed, why not target? Don't see why it has to get around hexproof and shroud (especially when most if not all other fight cards target).
Fodder Bomb - For red it feels more like "Sacrifice all Goblins".
Furywing Hellkite - I think it's fine as it is.
Heretical Ceremony - Spelling! 1R sounds good.
Roaring Lavavore - Doesn't really feel like a rare. Could be a 5/1 for RRR, Berserk 1RRR?
Wulgor Hellkite - Unlike the card above, this one won't be played in a monored deck. It looks fine to me. Wording: "Deals 5 damage divided as you choose among any number of target creatures."
Just an overarching comment from me: These cards (including your black rares thread) don't feel particularly "fresh." They encourage themes and play styles I might expect from as set 12ish years ago, minus the occasional bit of current rules jargon. Even the "New" ability words harken to very old cards and don't seem to invite much new design space, which I would hope to see on rares. Is your goal revisiting some of these older magic design archetypes?
To that point IcariiFA, I am an old school player and a fan of old school cards. So some of my designs have that feel to them. Also Madness is a fairly old ability now.
Dodge is based on the Ghustcloak creatures.
Berserk...well that's obvious.
Alpha felt new to me.
Valor is sort of Exalted and how I wish Banding really worked.
Cunning felt interesting to me.
Cunning isn't a great design space to work with as Mysticake pointed out. I agree there. Not to mention, you're pairing this in a set with madness which wants you to have things discarded and related enablers. That doesn't make sense. What is your design goal?
Valor is... where? I don't see it in either thread.
Alpha stands out as perhaps the most interesting of these. That said, it use here as nonbasic hoser is iffy. More pressingly though, if you have this a mechanic for your set you're going to want some pump abilities for red. You're madness dragon doesn't really get there with the unrelated hoops you'd have to go through to trigger it and no discard enablers.
Berserk is obvious and very swingy. It'll probably break things as presented here.
Dodge is...not black. Not at all. It really is unjustified. I don't really see design space to make it black either. Ghustcloaks are white for reason: Damage prevention is totally white.
Dodge might work on a low power defender in blue. But why dedicated a mechanic to it? It's straight damage prevention with a narrow loophole that next to no decks can force.
I'll ask again. What is your design goal for the set? What is the experience you're trying to create? Have you addressed that?
Avalanche Herald is, at best, an unblockable 3/3, which I doubt would see play in constructed. If your opponent doesn't have any nonbasics, it's a Hill Giant, which means it's mediocre in limited as well.
Guard Gomazoa was a one-off thing. There are, like, 12 blue cards in total that prevent damage. Well, and a couple that have abilities with a white activation cost.
Valor doesn't fit Blue at all either. I'd say it fits better in Red than Green, as well, especially given the name.
Bloodshed Arena feels like an awkward way to get around hexproof/shroud, and it's still almost always worse than Where Ancients Tread, which is a junk rare.
The design goal of the set is for the creation of new abilities in the existing color 'shards'.
The experience I'm trying to create is that players have to be aware of how their creatures attack and block. When to hold cards in hand, and when to use their spells.
I see Dodge as I see Unearth. Dodge is definitely not Black, but it forces your opponent to block with more than one creature to try to kill your creatures. Unearth, has no business being in Blue, and yet it is. Unearth is a strictly black ability.
Valor is the same way, I see it like I see Exalted. Exalted really doesn't fit the flavor of blue, yet it has it. Even black has Exalted, again, it doesn't fit, yet it has it.
Avalanche Herald 2RR
Creature - Elemental
Alpha - Whenever this creature becomes blocked, if its power is greater than or equal to the power of a creature blocking it, you may destroy target nonbasic land.
3/3
Avalaunch 1RR
Enchantment
Sacrifice a mountain: Put two 1/1 red Goblin creature tokens with haste onto the battlefield.
Bloodshed Arena 3RR
Enchantment
Whenever a creature with power 5 or greater enters the battlefield under your control, you may have that creature fight a creature target opponent controls.
Fodder Bomb RR
Sorcery
Destroy all Goblins.
Fodder Bomb deals X damage to target player, where X is equal to the number of Goblins destroyed this way.
Furywing Hellkite 3RR
Creature - Dragon
Flying
Madness 4RRR
When Furywing Hellkite enters the battlefield, if its madness cost was paid, other creatures you control get +X/+0 and gain haste until end of turn, where X is equal to Furywing Hellike's power.
5/5
Heterical Ceremony 2R
Enchantment
Whenever an opponent taps an artifact, that player sacrifices it unless they have Heterical Ceremony deal 2 damage to him or her.
Roaring Lavavore 1RR
Creature - Elemental
Trample, haste
Berserk 2RR (Whenever this creature attacks, you may pay 2RR. If you do, it gets +X/+0 until end of turn, where X is equal to its power. Sacrifice it at the beginning of the next end step.)
4/1
Wulgor Hellkite 5RR
Creature - Dragon
Flying
Cunning - When you cast Wulgor Hellkite, if you have five or more cards in your hand, it deals 5 damage among any number of target creatures.
5/5
Questions, comments, concerns, constructive criticism, conundrums?
Servien
Chaos' Realm
Escalation of Chaos
Tales of Cahdaria
Enigmatic Distrubance
Celestial Unveiling
Avalaunch is Goblin Trenches in one color, with no activation cost, and the tokens have haste. Probably too strong.
Bloodshed Arena is Where Ancients Tread with a couple of downsides (can't hit players, can kill your creature), which is pretty bad, even if it can sometimes kill creatures with 6+ toughness.
Fodder Bomb is Goblin War Strike with a downside, unless you're playing against Goblins, in which case it's a really strong hoser.
Furywing Hellkite's ETB effect is a bit too good. It's pretty much "you win" if you have a couple of other creatures out. It's also pretty strong when hardcast.
Heretical Ceremony isn't very strong. It's almost strictly worse than Null Rod and worse than Stony Silence.
I think Roaring Lavacore is a bit too strong. 4 power and haste for 3 mana makes it one of Red's most efficient 3-drops ever.
Wulgor Hellkite has the same problem that Saviors of Kamigawa's Wisdom cards had: it forces you to not play cards. This is especially bad in Red, which is the color that's most likely to empty its hand. For one mana more, you could just play Bogardan Hellkite, which is better in multiple ways.
Avalaunch - This could probably cost a bit more and have an activation cost.
Bloodshed Arena - It gets around hexproof and shroud.
Fodder Bomb - I was going for Goblin War Strike and Last Ditch Effort. Just something fun and funny.
Furywing - Maybe cost it one more? increase the madness cost? change the madness ability?
Heterical Ceremony - Maybe reduce the cost? Increase the damage?
Roaring Lavacore - Increase the cmc? increase the berserk cost?
Wulgor Hellkite - Cunning is all about when to play the cards you have in your hand. True, it forces you to keep several cards in hand, and red is very impatient. Maybe reduce the cost by a bit? 1 or 2 at the most?
Servien
Chaos' Realm
Escalation of Chaos
Tales of Cahdaria
Enigmatic Distrubance
Celestial Unveiling
Avalaunch - Should have mana activation cost. 2?
Bloodshed Arena - Indeed, why not target? Don't see why it has to get around hexproof and shroud (especially when most if not all other fight cards target).
Fodder Bomb - For red it feels more like "Sacrifice all Goblins".
Furywing Hellkite - I think it's fine as it is.
Heretical Ceremony - Spelling! 1R sounds good.
Roaring Lavavore - Doesn't really feel like a rare. Could be a 5/1 for RRR, Berserk 1RRR?
Wulgor Hellkite - Unlike the card above, this one won't be played in a monored deck. It looks fine to me. Wording: "Deals 5 damage divided as you choose among any number of target creatures."
Level 2 Judge
Token and Playmat Store
Beyond the Guildpact
Dodge is based on the Ghustcloak creatures.
Berserk...well that's obvious.
Alpha felt new to me.
Valor is sort of Exalted and how I wish Banding really worked.
Cunning felt interesting to me.
Servien
Chaos' Realm
Escalation of Chaos
Tales of Cahdaria
Enigmatic Distrubance
Celestial Unveiling
Valor is... where? I don't see it in either thread.
Alpha stands out as perhaps the most interesting of these. That said, it use here as nonbasic hoser is iffy. More pressingly though, if you have this a mechanic for your set you're going to want some pump abilities for red. You're madness dragon doesn't really get there with the unrelated hoops you'd have to go through to trigger it and no discard enablers.
Berserk is obvious and very swingy. It'll probably break things as presented here.
Dodge is...not black. Not at all. It really is unjustified. I don't really see design space to make it black either. Ghustcloaks are white for reason: Damage prevention is totally white.
Dodge does fit blue a bit, with creatures such as Guard Gomazoa.
Servien
Chaos' Realm
Escalation of Chaos
Tales of Cahdaria
Enigmatic Distrubance
Celestial Unveiling
Dodge might work on a low power defender in blue. But why dedicated a mechanic to it? It's straight damage prevention with a narrow loophole that next to no decks can force.
I'll ask again. What is your design goal for the set? What is the experience you're trying to create? Have you addressed that?
Guard Gomazoa was a one-off thing. There are, like, 12 blue cards in total that prevent damage. Well, and a couple that have abilities with a white activation cost.
Valor doesn't fit Blue at all either. I'd say it fits better in Red than Green, as well, especially given the name.
Bloodshed Arena feels like an awkward way to get around hexproof/shroud, and it's still almost always worse than Where Ancients Tread, which is a junk rare.
The experience I'm trying to create is that players have to be aware of how their creatures attack and block. When to hold cards in hand, and when to use their spells.
I see Dodge as I see Unearth. Dodge is definitely not Black, but it forces your opponent to block with more than one creature to try to kill your creatures. Unearth, has no business being in Blue, and yet it is. Unearth is a strictly black ability.
Valor is the same way, I see it like I see Exalted. Exalted really doesn't fit the flavor of blue, yet it has it. Even black has Exalted, again, it doesn't fit, yet it has it.
Servien
Chaos' Realm
Escalation of Chaos
Tales of Cahdaria
Enigmatic Distrubance
Celestial Unveiling