PRINCIPLES OF TIME TRAVEL

This book is, like The Tome of Halaster, a collection of appropriated knowledge acquired from many different cultures and planes over the millennia regarding the principles of time travel. Down deeper into the warehouse is a massive platform and device that clearly does not look like it's from the time you come from. This is probably how Cora travels from place to place, time to time. It looks demonic in nature, and not friendly at all. Looking closely at the machine, it appears it has been modified by the forces of Hell, as upon closer inspection - does not initially look like what Hell would normally posses. The book goes into great depth into how to use it, and the risks involved. 

One thing you note with a little alarm, the time travel device take a MASSIVE amount of power to operate, and is a one way trip once stepped through. Thankfully, Cora left VERY SPECIFIC instructions on how to return to approximately the time of when you began your journey into the Underdark.

So, he fought this too. Grianne says as the 5 gods are read outloud.

With this knowledge in hand, It is apparent that this next part of your journey involves travelling to different planes and trying to retrieve these coins. According to the text, each coin will grant a god like power that would indeed help in your destiny to destroy Umbra. Thankfully, the book on Time Travel also contains methods on planar travel. The text gives a brief description of each plane and it's "capital" where the god resides.

The Gates Of The Moon: Argentil (Selune): Located deep in the Astral Sea, the plane called The Gates Of The Moon is an endless ocean of luminous liquid light under an equally boundless night sky full of stars and a moon. The moon waxes and wanes but is always present. In the middle of the ocean is an island of stone with Selune's magnificent silver acropolis known as Argentil. Argentil is a place of beauty, quietness, and moonlight - a vast hall fashioned of shining silver. The ever-present moonlight hugs all beings and things, making them glow with a soft, silvery light on this plane.

The Deep Forest: Summeroak (Silvanus): Silvanus, The Forest Father, resides on a plane deep in the Outlands called The Deep Forest - in Summeroak. The Deep Forest is home to the greatest of all trees. It is a realm of thick and feral vegetation, as well as a rich and diverse wildlife. Dense and majestic canopies almost entirely blocked sunlight from reaching the ground below. The entire place is claimed by nature. There is no artificial buildings anywhere in the Deep Forest. 

Pandemonium: Winter's Hall (Auril): The realm of Winter's Hall is a frigid tundra fraught with violent winter storms, with winds rarely slower than 30 miles per hour. Visibility is only a few feet because of the extreme blizzard conditions. It is said that as one travels deeper into the realm, it grows colder and colder until the land is covered in a vast sheet of ice. It is said that there is no colder place in the multiverse, and anyone not taking shelter would take extreme damage from the bitter cold. Auril resides in Winter's Hall - a massive ice palace floating in the plane.

Mount Celestia: Dwarfholme (Marthammor Duin): Dwarfholme, the realm of Marthammor, is deep in the Astral Plane and located on the fourth layer of Mount Celestial. Celestia is the ultimate place of law and all that is good. All aspects of Celestia were beautiful and perfect; it is where the souls of many creatures of lawful good alignment go to after death. The seven individual layers form a colossal mountain that rises from an infinite sea of holy water on the bottommost layer, to the summit on the topmost layer. 

Acheron: Banehold (Bane): The Infernal Battlefield of Acheron is a plane far away, located in the Outer Planes - it is an eternal battlefield of endless conflict where unending battles take place across the entire plane between huge armies, with no chance of victory of cease-fire. It is a collection of massive cube worlds - it's capital is called Banehold, were The Master Commander, the Lord General Tyrant Bane resides and rules. They say to gaze upon his form drives a man insane.  This plane is currently locked in a war with Hell since the beginning of time, and the place where those who have died in battle eternally reside to never rest from war.

Chose your first destination when ready.

All hail.

"Undermountain will have to wait for now. Looks like we are to source the power of Gods in order to take on Halaster. I imagine finding him in Undermountain will prove easier once we return with the power of these coins...

We should plan and discuss this carefully. In this time and place- I think we have all the time in the world... We should go back, once we have the coins and stop the meteor attack if we can."

The basic jist of the master plan now is this:

1. Travel to each of the different planes in any order of your choosing, and get the coin in that realm. Doing so will level you all up and make you more powerful. Getting the coins in a certain order will be more beneficial to you as some planes are more dangerous than others. I will elaborate on this later tonight.

2. Return back to the Warehouse and use the time machine to travel back in time (to a point of your chosing) before Umbra destroyed the world.

3. Use the powers of the Gods to travel to the star and defeat Umbra.

Pretty simple.

"It definitely seems to be that way," Alessandra says idly in response to Ra'iik as she sets down the book, her eyes focused on Cora's writing on how to operate the machine. "Time travel... What a dangerous thing..." There were many things to take into account of all this, and even though it seemed that they had all the time in the world... "We should get to it then. Wasn't there an order in the tome? Selune, Silvanus, Auril... Perhaps we should do it in that order?"

Mother never told me about this. If Father has left us a gift to aid us, we must retrieve it.  Since I have established Grianne being raised by the forest deity that has a unicorn symbol and I cant spell, could I perhaps commune with them ?

I wrote this out to help you guys decide where to start first.

Yes, there is an order, more or less. Choose wisely.

Plane: The Gates Of The Moon
Location: Argentil
God: Selune
The planetars of Argentil are master space navigators and cosmic defenders. They possess astronomical knowledge unrivaled in any other realms. For eons, they have been one with the universe, and it's star children. They are up to date on all matters of the cosmos with it's beauty and it's chaos. Selune, The Lady Of Silver, they say, is part of the universe itself.
COIN: The bearer of the Coin of Selune would possess the knowledge of astronomical charts, navigation, star travel - and one would never get lost.
RISK: Low. While this plane is an endless sea of law and chaos, it is not inherently dangerous. Finding the coin would be the biggest challenge.

Plane: The Deep Forest
Location: Summeroak
God: Silvanus
The home of The Forest Father has inhabitants who's age rivals that of the planetars of Argentil. It is said that the natural and wild food that grows there is unlike anything in the multiverse. Wild, untamed, and wondrous. It's natural inhabitants live longer than the natural life cycle of stars.   
COIN: That which possesses the Coin of Silvanus is rumored to have no more need for sustenance, and halts the aging process to a near halt. 
RISK: High. The forest is unlike any natural wonder. It is primal, feral, and dangerous. To travel here without direction is to become forever lost - a permanent new residence of the wilderness.  

Plane: Pandemonium
Location: Winter's Hall
God: Auril
There is no place colder in the multiverse. Only the depths of the cosmos rival how cold this realm is. Located deep inside pandemonium, it is rumored that the inhabitants of this frozen and frigid wasteland have mastered a way to endure temperatures well beyond the limits of mortal comprehension.
COIN: The coin of Auril would grant someone protection from extreme cold. They say the bearer of this coin could survive in the depths of space and stay warm.
RISK: High. Without protection from the cold, mortals would not last more than a day in the bone cracking cold of this plane. Not to mention Pandemonium is one crazy place.

Plane: Mount Celestia
Location: Dwarfholme
God: Marthammor
Dwarfholme has dwarves living among the population that may possess the knowledge on how make armor that could withstand extreme punishment. The dwarves are renown for their crafting and handiwork. Only on this plane could a master crafter be found that would be able to forge armor worthy to protect one against the threat of Umbra. 
COIN: The coin of Marthammor would most likely grant a person the powers of divine protection that could possibly be able to withstand astronomical punishment, in addition to extreme heat and cold.
RISK: Low. This realm is Lawful Good with very, if any, threats to it. 

Plane: Acheron
Location: Banehold
God: Bane
The Eternal Battlefield of Acheron is most likely the plane where you will find augmented powers and skills that improve your fighting ability to destroy Umbra. The Acheronians are a strict warrior society that has appropriated technology from other realms in order to combat their mortal enemy: Hell.
COIN: The coin of Bane would possibly transform someone into a devastating melee warrior, imbued with the martial prowess and tactical strategy of The Lord Commander himself.
RISK: Moderate. This is a plane of constant war. Without protection, you will most likely be picked off one by one in the embroiling war. The Acheronians do not know you, and Hell's fury knows no bounds. 

The order I would suggest;

1. Dwarfholme 2. Winter's hall 3. Argentil 4. Banehold 5. Summeroak

Dwarfholme sounds like they would ally is towards the cause. The protection against heat and cold will help us gain the winter coin, which would help us withstand "space coldness". Then having the might of the Bane coin, we can visit the dangerous forest.

I would prefer summeroak be further up the list, but the general order doesnt matter to me in the end.

I like the order Afro posted because it makes the most sense c: we get the coins in an order that makes it possible for us to survive the other realms

That order is ideal. You’ll need protection from the cold to survive Winter’s Hall and the ability to not get lost in the great forest of Summeroak. Well done. Say your goodbye’s for the journey to save the universe begins with Dwarfholme.

With her home Forrest currently a pike of ash, Grianne has no goodbyes to make. She holds her new shield tight and is prepared for the journey ahead.

After talking among yourselves over a certain amount of time, you guys decide to journey to Mount Celestia, home of Dwarfholme, in the attempt to try and find the Coin of Marthammor to allow the forging of great armor that could withstand incredible punishment.The time machine, in addition to extremely limited time travel capabilities, has extensive abilities to take you from plane to plane and back to the warehouse. You should have no trouble reaching Mount Celestia, or any other plane, with the instructions and coordinates you're given. You prepare yourself for this journey of a lifetime, in an attempt to save everything you've ever known. You all step onto the platform and look at Nim as he works the controls. He takes a moment to work with OU812's programming, enabling him to cast a spell of return when you all are finished at Dwarfholme. With a single look of "good luck", he nods and hits the button to execute.

All you remember was the strangest tingly feeling and an overpowering flash of light, and from that moment on, you were no longer on Toril.

LOCATION: MOUNT CELESTIA
1000 YEARS SINCE THE DESTRUCTION OF TORIL
OBJECTIVE: FIND THE COIN OF MARTHAMMOR

You awake peacefully on a plain of perfect grass, the sun is in the sky and it's amazingly tranquil and warm. It's a perfect day in every way. You feel completely rested and feel no stress, no fatigue, even your mind is calm. You look to your left and see a sight that leaves you in complete awe. The single sacred mountain of Mount Celestia rises from a shining Silver Sea to heights barely visible and utterly incomprehensible, with seven plateaus marking its seven heavenly layers that you read about in the book. One of those layers is Dwarfholme. Gazing toward the peak fills you with complete and utter amazement, and you find yourself unable to move from wonder as never in your life have you felt more protected, more loved, more closer to everything that is good, heavenly, and just. This realm fills with you peace in every way imaginable.

(On each of the planes, I will present a certain number of challenges and their conditions that need to be overcome in order to win the coin. You are all strangers in a strange land and will not be able to waltz in, take what you want, and return home. You have never been here before and need to use your wits to win these objectives. At this part of the adventure, it gets much more difficult. If, at any point, any of these objectives are not met, you have lost and the campaign will end. There are no second chances to make a first impression, the stakes are very high, so work together, help each other, and get what you need to save the universe.)

THE CHALLENGES

NAVIGATING THE PLANE (ALL): It took two months to reach the base of Mount Celestia. You traveled through miles and miles of grasslands, gentle forests, rugged mountains, and tranquil rivers. Solars, dragons, archons, and phoenixes followed you curiously as you traveled. Everywhere you looked was beauty in such a heavenly form. You could easily see where Mount Celestia was, but I will need you all to make a DC5 Nature roll each to make sure you all didn't get lost, forever lost, in this heavenly land.
FINDING DWARFHOLME (ONE): You began your climb of Mount Celestia on the first level, Lunia. The base of Celestia was a surrounded by a massive body of water called The Silver Heaven, and it was named appropriately. Lunia is ruled by the great Archon named Barachiel, and along your climb you were intercepted by his curious, but friendly, lieutenants. You took this moment to introduce yourselves and ask which level Dwarfholme may reside. Because the natives of this plane are all Lawful or Good, chose a spokesperson. Make one DC5 Persuasion check to get directions. If this check is failed, you have misspoken and are escorted out of the realm. The mission is a failure.   
NEGOTIATING THE COIN (ONE): You managed to travel to the second level, named Mercuria, The Golden Heaven. Everywhere you look, a mysterious golden light permeates everything within it. Gentle hills and lush green valleys comprise this layer, dotted with small settlements of archons and other good-aligned beings. Mercuria is ruled over by the sword-wielding Domiel from the Golden Spire of Aurilon, a 400-foot-tall golden tower. You finally arrive in Dwarfholme after what seems like a year of travel. You are granted an audience with the rulers of Dwarfholme and are allowed to present your case. The dwarves are very willing to help, so have one person make a DC5 Persuasion check to get the Coin of Marthammor. Failure means you have acted disrespectfully, and have no hope of retrieving the coin. Game over.
CREATION OF THE ARMOR (ALL): With the coin in hand, you are led further up Mount Celestial to activate the coin's power. Chronias is the topmost and final layer of Celestia, also called The Illuminated Heaven. There is no real account or description of Chronias, as no entity that has entered has ever returned. You are asked to wait at the entrance to the layer, and were not allowed to go in. It is thought to be the ultimate goal of the inhabitants of Celestia to ascend the layers one by one in order to reach Chronias, where their souls will join with the essence of the plane itself. To say that, as visitors, you were allowed this high up was the greatest honor of your life. You waited patiently as the dwarves stood at the edge of Chronias and began to forge and chant as the coin's magic was enabled to created suits of armor unlike anything you have ever seen. You were asked to be reverent and silent as the process took place. I'll need everyone to make DC5 Religion checks to remain pious during the procedure. Should anyone fail, you will be found blasphemous and removed from the realm. Umbra wins.
GOING HOME (OU812): Thankfully, Nim gave OU812 very specific algorithms to follow once you guys obtained the coin. All you gotta do execute the stored spell in OU812's programming and you all should find yourself back in the Warehouse on the ruined planet of Toril. No help can be given on this task. It's all up to OU812. DC5 ARCANA to activate the portal and return home. Failure means you all get lost somewhere in the multiverse. A nat1 means you end up in the darkness of space and all die immediately.

OU812 slaps Evrik on the back...."Looks like you're home, amigo!  Let's go find this master craftsman who can build you some god-ass-kicking armor!"

Mount Celestial challenges are up.

It's all up to you guys. Role play as much as you want. This is truly the beginning of an amazing journey.

Nature check! 15

Grianne shrinks back when the group is approached. She is not comfortable with new people.