MTG Salvation

I don't think adding half an Armageddon to a card is a good way of weakening it. If you don't want to add to the cost, then maybe just make the effect less drastic. How about "Exile all nonland permanents. Each player draws a card for each permanent he or she controlled that is exiled this way." That could probably pass muster at 3WU or so.

As far as Ancestral Genius goes, I actually think the correct mana cost for it is xxBBB. A blue tutor is not totally outlandish, but it's just a better fit for black. You could maybe get away with xxBB as the cost. It would be more versatile than Diabolic Tutor for the same cost, but Diabolic Tutor is just an okay card, and the one-turn delay in the effect does mean something. Also, there's no need to reveal the cards - they will be revealed while exiled anyway.

The "battlefield or stack" clause is a huge improvement in terms of game balance. I think it's actually fine that way, as you can't get the mana unless you get that card in play anyway. Would be fun on a Ball Lightning-style creature. Furthermore, this allows you to put larger (although still not huge) Refund amounts on more expensive cards.

I'm not sure why the bottom-of-library part or the first-main-phase part are there, though. I would try to find a way to ditch those, as they seem superfluous and could create memory problems. Here's a suggestion:

Refund RRRR (Whenever this card would be put into a graveyard from the battlefield or stack, you may exile it with a refund counter instead. If you do, it gains "Remove a refund counter from this card while it is exiled: Add RRRR to your mana pool.")

That's still a bit wordy, so there may be a better way to do it, but I think it's preferable for the card to remain visible and avoid memory issues.

Mistmaw 1UB
Creature - Spirit
Sacrifice a creature: Switch ~'s power and toughness until end of turn.
1/5

Chthonic Wurm 3GGGG
Creature - Wurm
If ~ would deal damage to a creature, exile that creature instead.
You may play cards exiled with ~.
6/8

Next: Crown of the Goblin King

Vine Wielder 3G
Creature - Elf Warrior
Deathtouch
1G, :symtap:: ~ deals 1 damage to target creature with flying.
1/4

Conclave Guardian 6GGGG
Creature - Wurm
Convoke
When ~ is put into a graveyard from the battlefield, put seven 1/1 green Saproling creature tokens onto the battlefield.
7/7

Next: Torrent of Souls in Fifth Dawn

Strength of Soul + Aether Tide

Tide of Strength xG
Instant
As an additional cost to cast ~, discard X cards.
Creatures you control get +X/+X until end of turn.

Quote from erock98

Next: ABC123

Mighty Metal Man ABC123
Artifact Creature - Construct
5/5

Next: R

Twisted Foresight 1UU
Sorcery
You may cast a suspended card owned by an opponent.
Cycling 2

Hand-Cranked Generator 3
Artifact
:symtap:, Tap an untapped creature you control: Add to your mana pool.

Sprout is already the name of a card, and the costs are just too low. I would play this card for the Transmute alone...the strong flashback ability is just a bonus. I would rather see this card have Transmute 2G or Forestcycling 2, so as not to be strictly better than Sylvan Scrying. Ok, so it has some issues, but more importantly, this does look like a really fun card, so I'm going to rate it decently anyways. 7/10, and would be 10/10 if developed appropriately.

Rod of Glaciers 7
Artifact
:2mana:, :symtap:: Tap up to two target permanents.
Recall - artifact (:2mana:, Discard this card from your hand: At end of turn, return target artifact card from your graveyard to your hand if it was put into your graveyard from anywhere this turn.)

Next: A split card

Kor Traitor:sym2w::symw:
Creature - Kor Soldier
:1mana:, :symtap:: Target non-Equipment artifact card in your graveyard gains "Unattach an aura from a permanent controlled by an opponent if it has been enchanted since the beginning of your last upkeep: Return this card

Kor Traitor :sym2w::symw:
Creature - Kor Soldier
:1mana:, :symtap:: Target non-Equipment artifact card in your graveyard gains "Unattach an aura from a permanent controlled by an opponent if it has been enchanted since the beginning of your last upkeep: Return

I like it with the colorless mana. Vulnerability to removal is the primary reason that mana guys can be cheaper than Rampant Growth. If it gives colored mana and can later chump block if necessary, then it's just way better than most other accelerators. Even with colorless, I'd consider it stronger than Boreal Druid, as the 1 power isn't terribly relevant anyway.

Extremely strong with Brainstorm, Burning Inquiry, etc. That's probably fine, though.