Pyramid of Sorasa
6
Artifact
Monument 5 (~ enters the battlefield with 5 Monument counters. ~ is indestructible as long as it has monument counter on it. Whenever you are dealt damage, remove that many monument counters from this artifact as well. When ~ has no monument counter sacrifice it)

Tap an untapped creature: Add a monument counter to ~.
During your upkeep if ~ has 8 or more monument counters, you may return target creature card from your graveyard to the battlefield.

I don't know what the answer is, and I doubt we'll know before a month's worth of Design. That said, mummify is a neat enough mechanic that I would start there, with the fall-back plan of Vengeful Pharaoh in mind. I mean, chances are we'll discover something different and better than both options, right?

I feel that Mummies would be easier to balance if the mummification didn't happen immediately and automatically. It could be an ability that you activate from the graveyard that you had to pay a cost for (such as a mana cost or a discard cost) or satisfy some condition for.

Laws, as far as I see them executed in game, would work like World Enchantments without the rules baggage - a broad condition effecting gameplay.

You're pitching rube goldberg devices, not overarching themes. They don't feel legal.

Example (on phone so wording will be off) -
Law of Speed - R
Enchantment - Law
Creatures you control have haste.
Whenever another law etb, sacrifice ~.

Law of Brutality - 2RR
Enchantment - Law
At the end of combat, if three or more creatures died, untap all creatures you control. There is a second combat phase.
Whenever another law ETB, sacrifice ~

The problem is that in my fist submision I was told:

Tablet of the law of war
CMC = 3 Artifact
4,tap: all attacking creatures you control must be blocked this turn if possible.
[The middle kingdom has never lost control of the tablet of the law of war in all known history]

This is a reasonable top-down rare, but it's certainly not a common.

Therefore I was trying to see how I could introduce those. I might be too in love with the tablets however. Do you think they have potential or should I just scrap them?

If they're just a series of cycles, they'll be prevalent enough in the packs. Also, by adding a limiting clause, you defeat the purpose of making them more available. It really just feels like you're jumping through a lot of hoops to do World Enchantments.

Artifact – tablet
Tablet (You cannot cast a tablet if you already control one)

But I would rather hear your oppinions out.

I have made them artifacts, and will give common and uncommon ways to interact with these in all colors (white will get an artifact exiling oblivion circle, in the way of entombing what we cannot control, red will get manic vandals smashing artifacts, black will get counter removal, blue bounce and green artifact destruction)

I would like to hear your ideas out on this… Here are some examples, please feel free to critique and tell me if this is not a path worth exploring and if so, why.

I bend the color pie a tiny bit to keep the flavor of afterlife related efect in mind. I also have not fixed the mana costs at all.

Table of the Law of War 3R – special (rare)
Artifact
Whenever a creature dies durring at the end of the combat phase put a Law counter on ~.
At the beggining of your upkeep, if 10 or more Law counters on ~, remove all counters from it, and return all creatures from all graveyards into play. They have haste. Exile them at the end of turn.

This one plays pretty well with viashino scout effects… you get them back into your hand while your opponent gets to block, fuelling your table of law back…

Table of the Law of Heat 3R – special (common)
Artifact
Whenever a creature dies from non-combat damage, ~ deals 2 damage to the creature's controller.

Tablet of the Law of Change 3R - special (uncommon)
Artifact
Whenever a player casts a spell, he discards his hand then draws that many cards

Table of the Law of Protection 3W - special
Artifact
Whenever a creature dies, if you have not been dealt damage this turn, put a Law counter on ~
Whenever a source would deal damage to you, or to a creature or planeswalker you control, reduce that damage by the number of counters on Law of protection.

Table of the Law of Rememberance 3G special (uncommon)
Artifact
Whenever a creature dies, his controller may search his library for a copy of that creature, reveal it and put it in his hand.

Table of the Law of Embalment 2WBB (mythic)
Creatures you control have mumify.
(Mummify : When ~ dies, return it to the battlefield with a mummified counter. Creatures with a mumified counter loose all abilities. It's a zombie in addition to its other types.)

Table of the Law of Pain 3B - special

Table of the Law of Ignorance 3B - special

Table of the Law of Growth 3G - special

…

Pest-Ridden Crop G
Creature - Plant
At the beginning of your upkeep, put a growth counter on ~.
Remove three growth counters from ~: put a 1/1 green insect creature token onto the battlefield.
1/1

Sobek Farmer 1G
Creature - Crocodile Druid
At the beginning of your upkeep, put a growth counter on ~.
Remove three growth counters from ~: Add GGG to your mana pool.
1/3

Field Irrigator 1U
Creature - Human
At the beginning of your upkeep, put a growth counter on target permanent you control.
Remove a growth counter from ~: Target creature gains islandwalk until end of turn.
1/1

Devout Patrician 2W
2/2 Human
Afterlife — When ~ is exiled from your graveyard, draw a card.

Mummify (when this dies, return it to the battlefield with a mummified counter and no abilities. It's a zombie in addition to its other types.)

Curse of the Undead 1B
Enchantment (U)
Whenever a zombie creature you control dies, each opponent loses 1 life.

At the beginning of each end step, if a card was exiled this turn, <effect>.

There are a number of ways this could be tweaked, but the important bit is that it only triggers once per turn.

While we can carefully design exile-counting cards to avoid overpowered combos with these mass-exile cards, it would still leave a permanent design restriction for the future. Design would lose "massive exile" as a balancing tool for future cards.

Tumra River Guardian 2GG
3/3 Crocodile Warrior (unc)
Protection from blue
Mummify (When ~ dies, return it to the battlefield with a mummified counter and no abilities.)

Twisted Effigy 2BB
6/6 Horror (rare)
~ has -5/-5.
Mummify (When ~ dies, return it to the battlefield with a mummified counter and no abilities.)

Counting the cards in your exile zone starts to creep a little bit into caring-about-the-Absolute-Removed-From-The-Game-Forever problem a bit. I wouldn't veto it, but I wouldn't vote for it.