"Island Clouds, as well as Sea Clouds, are created when a compound called Pyrobloin is ejected into the air by volcanic eruptions and comes in contact with the water vapours. The density of water vapours determines where an Island Cloud or a Sea Cloud will be formed. If the density of water vapours is high enough, Island Cloud will be formed, but they are very rare. This is why there are not a lot of Sky Islands in the world, and most of the ones we know about are situated in the Grandline or over the Calm Belt..." Robin patiently explained things about Sea Clouds and Sky Islands to the crew, who did not know anything about them. "Also, the compound Pyrobloin is found in Seastones, and so, the Sea Clouds have the same properties as the Blue Sea."
Nojiko, who was waiting down everything that Robin told them, nodded her head at the end of her words and then excitedly raised her head to ask her next question, but Nami beat her to it.
"How many Sky Islands do you know about?"
"Four. And the one we are going to now will be the fifth one." Sin told them as he walked over, and then sat on top of the railing, looking at all of them. "The Sky Island that the Black Family ruled over is called Avalon, and that's where my Palace is. Elgios is the fallen Sky Kingdom where I found Duraakh." He pointed at the Blood Sword he was wearing on his back. "And there is another Sky Kingdom called Valoria, quite close to Elgios, and there are people living on it, who have wings on their backs."
"And the fourth one?" The Orange-head excitedly asked, and the smile on Sin's lips thinned a little, which the keen ones immediately noticed.
"Birka. People with Wings inhibit it as well. And that Sky Island is not too far from here. It is situated on the Calm Belt which separates Paradise and South Blue."
"Do you think there could be people living on the Island we're going to?" Lily hopefully asked, and the two Blacks smiled at her.
"Maybe."
"We'll see."
"How are we going to get up there?" Nami asked the question for the umpteenth time, still as excited as the first time she had asked the question two nights ago.
"Knock Up Stream." Sin grinned, and the one who was very familiar with that looked at him in disbelief.
"What?" Vigaro's face paled as soon as he heard the name. "It will destroy the ship!"
"Wouldn't be the first time we would ride it in a ship. And the last one we used was quite a fragile ship." Robin giggled. "It is the fifth day since the last Knock Up Stream in this region. It should appear again today."
Sin looked up at the dark clouds in the sky and then at the small opening he saw in them. With his knowledge about Sky Islands, he knew that the patterns of the Knock Up Stream were fairly predictable once it aligned with the fossilised Clouds such as the one above their head.
And even if he did not know about these things, he could still sense with his Observation Haki what was happening at the sea bed.
"Come." He suddenly looked at Vivi and Nami, and both of them immediately walked up to him and allowed him to pick them up in his arms.
"Brace yourselves," Robin told them and then looked at Bepo, who immediately rushed to the helm. "Don't fall off the ship." She warned, tensing them up, and when they felt tremors in the sea, their hearts started racing in anticipation.
Yamato excitedly rushed up to the forecastle, following Sin, and then grabbed the railing ad she looked down.
By the time the ship started rising, everyone, except for Bepo was on the Forecastle Deck, holding on to the railing, and against their wills, screams escaped their lungs when they were suddenly shot up into the sky at a breathtaking speed.
"So, this is the Knock Up Stream!" Yamato laughed as she saw that they were sailing a water pillar up in the sky, and Sin, who had been reading Oden's Logbook in the last two days, knew that the Oni Girl was excited about seeing if the place they were heading to was the same as the one that Oden visited with Roger Pirates.
Those, who were worried about the ship, relaxed when they realised that the Black Pearl was sailing up the Knock Up Stream without any issue.
It took them a few minutes before they entered the clouds, and the Knock Up Stream kept pushing them up until it lost its force, just as they made it out of the counter layers, and they all panicked when the ship started falling.
"What?" Vigaro looked in disbelief when he found that the ship, which it gut the clouds, did not start sinking.
"Welcome to the Cloud Sea." Sin grinned as he looked at the White vastness, and everyone held their breaths as they took the sight in.
"The Log Pose is still pointing up." Nami, who inadvertently looked at the Log Pose, showed it to him, and he smiled at her.
"Well, that just means that we will have to find a way to get to the second Cloud Sea." He grinned and looked up, starting at the White Sky.
"Another Knock Up Stream?" Vivi cutely tilted her head, and he laughed at her question.
"No. There are no Knock Up streams here." He told them and increased the Domain of his Observation Haki. "On the left."
As soon as he said those words, Nami immediately looked in the said direction with her spyglass, and her mouth cutely dropped open at what she saw.
"There's a waterfall!"
"Show me!" Vivi excitedly took a spyglass and looked through, and she seemed shocked by the sight. "Woah..."
"Bepo!"
"Aye, Captain!" The Helmsman of the Black Pearl turned to ship towards the Waterfall, and when they got close enough, everyone else got to take a good look at it too.
"Do you want to have some fun?" Sin mischievously asked when he spotted certain bubbly hills around the Waterfall, and Yamato was the first one to respond.
"Yes!"
"Let's go then." He grabbed her rushed towards the nearest bubbly hill, and then threw Yamato right into it.
"Woah!!" The girl excitedly exclaimed when she fell and then bounced off its surface. "It's made of rubber!"
"No, but it has rubbery properties." Sin chuckled as he bounced together with her, and then laughed heartily when he heard the others complain.
Since everyone wanted to have some fun, they decided to stop for a while, and the crew spent a good few minutes playing with the bouncy clouds. It was then that they finally realised something.
"It's hard to breathe here," Pascia commented, struggling to find the oxygen, as the air was too thin at this height, and except for Sin and Robin, everyone else was struggling too.
"Sit down and try to control your heart rate. Don't exert your bodies too much..." She instructed, and those who were feeling the worst complied.
The stronger ones managed to acclimatise themselves quickly, when the Black Pearl finally made it past the Bouncy Clouds, they arrived at the Gate with a cloudy snake-way that led up into the upper sky.
"How are we going to sail up there?" Kuina frowned, and then looked around the Gate, spotting an aged lady who was walking towards them.
"She has wings!" Vivi surprisedly said, and those who were seeing a Sky Person for the first time were quite intrigued.
"I am Amazon, the Gatekeeper of Heaven's Gate. Are you here for sightseeing or fighting?" The old Woman asked, and they all looked at her in confusion.
"Sightseeing," Bonney answered.
"And how many of you are there on the ship?"
"16."
"Just 16?" She doubtfully looked at them and then at their massive ship.
"We are only 16." The pink-head nodded to her.
"Okay. That will be 16 Billion Exotols if you want to enter the gate and reach Skypiea."
"16 Billion?!" Nami freaked out as soon as she heard 16 Billion. "We are not giving you anything!"
"Okay."
They all deadpanned at how easily the old woman accepted her words, and Nami took a deep sigh of relief.
"We don't have Exotols on us, and I am sure Berries are of no use to you." Sin smiled at the woman and then used his Haki to Tame one of the Cloud Sea Kings to come to and take them to the Snake Way. "Don't panic." He told them when a giant crab lifted their Ship on its back, locking it in place with the spikes on its shell.
The old Woman curiously looked at the creature and then at them, and a sinister smile crept on her face, which spooked the younger girls.
"What?" Nojiko frowned.
"You are going to enter Gate without paying the toll."
"And?"
"Nothing. How can an old woman like me stop you?" She said.
Before they could respond, the Crab started moving, taking them up the Snake Way, and they all looked at their Captain when he suddenly started chuckling.
"What?" Bonney curiously looked at him.
"She just cursed us that God's Wrath may fall on us for illegally passing the Heaven's Gate," Robin informed them, giggling.
"What?" Nami looked quite unsettled after she heard those words, and she subconsciously gulped in fear.
"You don't have any questions about the Sea Beast?" The younger Black immediately took her mind off the dreadful thoughts, and the orange head's eyes widened in realisation.
"I didn't think there would be Sea creatures here."
"Well, there are a lot of them, and Cloud Fish are usually very tasty." Bonney grinned, looking forward to having a feast once they reached the Island called Skypiea.
"What's an Exotol?"
"It's a currency used on Sky Islands. Birka uses it too. 1 Berry equals 10,000 Exotols." Robin answered.
"Oh. So, she was asking for 1.6 Million Berries?" Nami looked at her in surprise.
"Yes." She nodded.
"Well, whatever. We are Pirates. Why should we pay her?" She grumpily said, and they all laughed at her words.
Unbeknownst to them, the Blackstar crew was heading towards a destination where they were going to face an enemy whom they would forever remember.