I’ve been inspired by @gabriek’s fantastic topic on buffing one card per faction. Thus, I’ve created this topic to air-out more design ideas for improving unplayed cards in constructed (in order to support current constructed archetypes, or develop weaker ones).
As such, I’ll be chiseling away at each card until I’ve come to some level of satisfaction. In the meantime, I’d love to hear what you all think of these proposed changes (i.e. have I gone overboard, or missed the mark entirely?). Also, feel free to share your own buff proposals as well!
Lastly, this topic is not open for philosophical debate of if/why bad cards are necessary, or a discussion of direct vs. indirect buff paradigms. Those can be entire topics in themselves. 
Buffing Project 1.0: Lyonar, Songhai, Vetruvian RDs completed
Lyonar
Sky Burial: Cost 3 → 2
- DoS introduced a lot of design redundancy, and this change would be an effort to better distinguish this card from Decimate (and Martyrdom, to a lesser extent).
Auryn Nexus: “Give a friendly minion +3 Health.” → “Give a friendly minion Zeal: Gains +5 Health.”
- The suggested change would (1) Improve and open up design-space for Zeal synergies, (2) Improve health benefit to bolster the card seeing any play at all (but counter-balance via the dependence on Zeal), and (3) Give Zir’an more potential to benefit from her BBS.
Sunstone Templar: Cost 2 → 4; Stats (1/4) → (3/5)
- As a 2-drop, this is plainly out-performed by Azurite Lion and Windblade Adept. Moving it to a different Cost/Stat bracket may allow its ability to shine.
Ironcliffe Heart: “Transform a friendly minion into an Ironcliffe Guardian.” → “At the end of your next turn, summon an Ironcliffe Guardian nearby your General.”
- Again, DoS brought too much design redundancy, and this would be an effort to actually distinguish the card while reducing its drawback (4 mana + “sacrificing” a minion). Instead, here you pay 4 mana for an Ironcliffe Guardian that is effectively Stunned and not Airdropped. For Zoo/Tempo Lyonar, it fits much better than a regular Ironcliffe Guardian (thus hopefully bolstering/better defining the archetype).
Songhai
Artifact Defiler: “Destroy all artifacts on the enemy General.” → “Destroy all enemy artifacts. Draw a card for each artifact destroyed” OR “Destroy an enemy artifact. Draw a card for each of its durability.”
- This sees (and has seen) no play, as multiple artifact usage is virtually nonexistent. Adding a card draw element would encourage its use above Rust Crawler, and could therefore turn it into an interesting tech card in an artifact-heavy meta.
Saberspine Seal: TBD →
- The nerf has left this card extremely redundant, as it simply acts as a strictly more restrictive (i.e. worse) Phoenix Fire now. That said, I struggle to see an obvious buffing route without reworking the card entirely. I’ll come back to this one later.
Jade Monk: TBD →
- Significant design redundancy with Battle Pando. I think this would require a similar rework. I’ll come back to it later.
Storm Kage: TBD →
Ace: Add “Cannot move.” OR “Can only move one space.”
- A rather obvious and prevalent suggestion. I don’t see the drawback of at least testing this buff amongst a faction minion that sees no play. Non-or-limited movement also feels flavorful due to the whole
thing. 
Sworn Sister Alkyone: “Spells you cast that deal damage deal +1 damage.” → “Whenever one of your spells deals damage, add a Mana Vortex to your action bar.”
- Another issue of DoS’s design redundancy: Crescent Spear simply eclipses this card. Thus, a rework entirely. Given Mana Vortex’s heavy nerf, why not now integrate it via ‘two birds, one stone’?
- Now that I think about it, I might like Mist Walking even more as the generated card (further bolstering Spellhai/Controlhai playstyles).
Mist Walking: “Teleport your General up to 2 spaces.” → “Teleport your General up to 3 spaces. Lower your General’s attack to 0 until the start of your next turn.”
- Gives Controlhai/Spellhai a more effective escape tool (+ supporting spell synergies) while also counter-balancing concerns of Mask of Shadows abuse.
Mask of Shadows: “Your General gains Backstab (4).” → “Whenever a friendly minion with Backstab deals damage, draw a card.”; Cost 2 → 4
- This card has seen no play since the nerfs to both it and Mist Walking. In all honesty, I think the fundamental concept behind the design is flawed. The ability to set-up a Backstab situation for your own General is both very rare and risky (as the artifact will likely be gone by next turn if you’re right next to the enemy General and their minions). Given the high risk and rarity of the situation, the pay-off needs to be incredibly high, which it is not. However, if you make the reward too high, then you lend gameplay to highly polar, non-interactive outcomes. Thus, I would argue for a rework entirely.
- That said, I’m very uncertain of the suggested change. I wanted to go the angle of bolstering the BackstabHai archetype, but I’m not sure if this would be the way to go about it (especially the cost). I’ll revisit it later.
Vetruvian
Siphon Energy: Cost 0 → 1; “Dispel an enemy minion nearby your General” → “Dispel an enemy minion nearby your General. Draw a card.”
- The nerf, while better aligning with Vetruvian’s proximity theme, has butchered this card’s playability. To improve its playability, while maintaining the theme, why not integrate Vetruvian’s tried-and-true card draw? It certainly still pales in comparison to Emerald Shroud (or even Rae), but it would at least be a step in the right direction.
Orb Weaver: “Opening Gambit: Summon a copy of this minion on a nearby space.” → “Opening Gambit: Give nearby friendly minions Forcefield.”; Cost 3 → 5; Stats (2/2) → (4/5)
- With Pax, this is another victim of DoS’s design redundancy. The proposed change is honestly just a shot in the dark. Many things could be tried, but overall the redundancy needs to be addressed.
- Other possibilities:
- Opening Gambit: Cast Sand Trap on an enemy minion.
- While this minion is on the battlefield, all enemies may only move 1 space.
- Dying Wish: Draw a random artifact from your deck.
- Opening Gambit: Equip a random artifact from your action bar.
Mirage Master: Cost 4 → 3; “Opening Gambit: This minion transforms into a copy of an enemy minion.” → “Opening Gambit: This minion transforms into a copy of an enemy minion and takes double damage.”
- This minion sees so little play that I forgot about its existence. Why not drop the cost and commit to the ‘illusion’ flavor?
- Another possibility would be something akin to Faceless Shambler, though I would have no idea how to word that.
Sand Sister Saon: “Your General has +1 Attack.” → “Costs 1 less for each artifact you have equipped this game.” Stats (3/4) → (3/5)
- +1 Attack is so incredibly underwhelming (+ pitiful stats), especially in comparison to the other Sisters. The proposed change is subject to heavy revision. I just wanted to get something on the table.
Corpse Combustion: TBD →
- This is one of those gray areas in which the card, without direct buffs, can become completely viable if CPG prints more high-quality Dying Wish minions. Otherwise, this would need a reworking. I’ll come back to this.
Fountain of Youth: Cost 2 → 8; “Restore all friendly minions to full Health.” → “Restore your General to full Health.”
- I admit, this one is extreme. I toyed with much more benign buffs like the tried-and-true “Draw a card”, but it still felt too redundant with Inner Oasis. Thus, why not give Control Sajj some sort of late-game insurance? At 8 mana, I’m not even sure this would see play due to the supreme
tempo loss.
Time Maelstrom: Cost 3 → 2
- A simple and straightforward push. Why not throw Artifact/Combo Vet a bone?
- Other interesting & flavorful rework considerations (focusing on time mechanics):
- “Return ALL minions to their action bars.”
- “Return ANY minion to its action bar. It costs ‘X’ less.”
- “Destroy all mana crystals for BOTH players.”
- “Destroy an enemy mana crystal. Draw a card.”
Scion’s Third Wish: “Give a friendly Dervish minion +3/+3 and Flying.” → “Give a friendly minion +3/+3 and Flying.”
- The Dervish restriction isn’t seen on either of the other two wishes, so having this be the odd-one-out is strange from both a flavor and design perspective. Removing this strange restriction may prove enough to support a Zoo/Buff Vet. On the other hand, it may be too good?
Sand Howler: Cost 3 → 6; Stats (3/3) → (5/8)
- The 3-mana slot is simply too crowded with Obelisks, Falcius, Wildfire Ankh, Zephyr, etc. Movement to higher cost/stat bracket may help it shine. However, I’m not entirely satisfied with the cost/stats. May come back to this later.
Abyssian (WIP)
Dark Seed: TBD →
Blood Siren: TBD →
Night Fiend: TBD →
Blood Barronette: TBD →
Arcane Devourer: TBD →
Shadow Nova: TBD →
Inkhorn Gaze: TBD →
Echoing Shriek: TBD →
Wraithling Fury: TBD →
Magmar (WIP)
Tremor: TBD →
Veteran Silithar: TBD →
Wild Inceptor: TBD →
Visonar: TBD →
Mind Steal: TBD →
Dreadnought: TBD →
Flaming Stampede: TBD →
Vanar (WIP)
Mesmerize: TBD →
Winter Blade: TBD →
Boundless Courage: TBD →
Lightning Blitz: TBD →
Huldra: TBD →
Wind Sister Maia: TBD →
Wouldn’t change it too much, maybe buff it’s stats a tiny bit if you feel it’s really needed?
I also agree with the Mask of Shadows rework idea, I think that’d make a lot more sense than how it is now.