Modern Horizons Spoilers

[Barook]

Best way to dump artifacts into the yard?

[FourDogsinaHorseSuit]

Best way to dump artifacts into the yard?

Mesmeric Orb - Besalt monolith?

[Poron]

you need a Time Warp with flashback for that

[Mr. Safety]

you need a Time Warp with flashback for that

Hold my beer...

[FourDogsinaHorseSuit]

Best way to dump artifacts into the yard?

Treasure hunt, 24 artifact lands, new mulligan rule, and your discard step.
I call it: All land belcher.

[Barook]

Damping matrix - Besalt monolith?

You probably meant Mesmeric Orb, but yeah, that works.

[FourDogsinaHorseSuit]

You probably meant Mesmeric Orb, but yeah, that works.

My bad

[Barook]

More spoilers:

[Poron]

Hold my beer...

how do you summon that from GY?

[morgan_coke]

This looks innocous, but I feel like it will be an issue eventually:

Universal Automaton 1
Artifact Creature - Shapeshifter
Changeling
1/1

Common

Also, this is just kind of hilarious if you remember Recall

Reap the Past XRG
Sorcery
Return X cards at random from your graveyard to your hand. Exile Reap

Rare

[Barook]

This looks innocous, but I feel like it will be an issue eventually:

Universal Automaton 1
Artifact Creature - Shapeshifter
Changeling
1/1

Oh no, more cheap Eldrazi to drop with Eye of Ugin!

I also misread Ephemerate, thinking it had Retrace instead of Rebound, making it pretty meh.

Edit: More cards:

[BenBleiweiss]

Fixed Dark Depths.

[Gheizen64]

Geomancer's gambit could have easily cost RR , not sure why a worse spreading Seas had to cost 3. Well beside the fact that Red has to suck.

[rufus]

Magmatic Sinkhole (5 damage to creature or planeswalker, R5 delve) is going to see fringe play. Delve is just that good.

[Phoenix Ignition]

Fixed Dark Depths.

But why is it blue?

[BenBleiweiss]

But why is it blue?

Because it's sad it isn't a land.

[Bosque]

The changeling one drop to enable the changeling double strike for 2 mana on curve is here (Universal Automaton). I think with all the changelings in this set, there may be some interesting developments coming with a number of tribal decks. I could see Humans, Spirits, Wizards, Slivers, Merfolk and probably a pile of others that I'm forgetting use some of these cards.

[ReAnimator]

But why is it blue?

Because this enchantment is the spell that is sleeping Marit Lage and keeping her subdued.
Break the enchantment and she wakes up all angry.

[FourDogsinaHorseSuit]

Fixed Dark Depths.

Looks like a change to token templating?

[Mr. Safety]

how do you summon that from GY?

It doesn't have flashback but it's a repeatable Time Warp, and cheap in a deck that already wants tons of artifacts in it. It isn't perfect, but it synergizes with Mirrodin Besieged by conveniently putting artifacts into the graveyard to satisfy it's 'win the game' clause.