Cloudians are, for the vast majority, Fairy-Type WATER monsters that are immune to destruction by battle but also self-destruct if they are in face-up Defense Position. The “Cloudian” archetype focuses on distributing Fog Counters and then utilize them in order to enable certain effects that range from monster to backrow removal
Generally Cloudians have very low stats, with Cloudian - Eye of the Typhoon, the Boss Monster of the archetype, so it’s very difficult to finish off the opponent, but at least in Duel Links they don’t have to work with 8000 Life Points.
These three monsters all have pretty powerful effects, but, in order to activate them, you’re going to need Fog Counters; For Acid Cloud and Cirrostratus you can’t utilize Fog Counters from anywhere else on the field to activate these effects, they have to be attached to these monsters.
These “Cloudian” monsters gain Fog Counters equal to the number of “Cloudian” monster on the field (including them).
Cloudian - Altus forces your opponent to discard a random card, which is great when you want to activate a Spell/Trap card and Wiz, Sage Fur Hire is on the field, but he needs 3 Fog Counters from anywhere on the field to do so;
Cloudian - Cirrostratus and Cloudian - Acid Cloud can destroy a monster and a Spell/Trap Card on the field respectively at the cost of 2 Fog Counters, they allow you to clear the board and chip away at your opponent's resources.
With The Sanctuary in the Sky face-up on the field you will not receive battle damage from battles involving your Fairy-type monsters. This allows you to safely keep your Cloudians in attack position without suffering from battle damage because of their low stats.
You can discard Zeradiasm, the Herald of Heaven to search out The Sanctuary in the Sky. Zeradias himself can be used as a beater, but will only stay on the field as long as The Sanctuary in the Sky is face-up.
On it's own The Sanctuary in the Sky only protects you from battle damage. But aside from that it brings with it great support cards, one of the best of which is Divine Punishment. Use Divine Punishment to negate any key card effects your opponent activates and destroy them to slow down your opponent's strategy.
Popular cards you can negate to disrupt your opponent are Amazoness Onslaught, Vampire Kingdom or Vampire Grace, The first Fur-Hire monsters summoned.
Cloudian Squall puts Fog counters on every face-up monster on the field once per turn. With 2 Cloudian Squalls you can use Cirrostratus and Acid Cloud to destroy a monster or backrow card respectively once per turn.
Cloudian Squall will also put Fog counter on your opponent's monsters. Since Fog counters will dissappear when the monster is destroyed, prioritize removing Fog counters from your opponent's monsters when using Altus to make full use of them. And Since Altus does not have "once per turn" mentioned in his effect, you can keep forcing your opponent to discard until they deplete their hand so long as there are enough cloud counters on the field.
With such low stats sometimes even Wall of Disruption or Mirror Wall wouldn’t be enough, so going for a less common card such as this one, that wouldn’t even make Treacherous Trap Hole impossible to activate after being sent to the Graveyard, is a great choice.
Fog Control is (unfortunately) the fastest way you have of getting Fog Counters on the monster you want; there are arguably better options when it comes to simply distributing them on the field, but, since Cirrostratus and Acid Cloud need to have the counters attached to them in order to activate their effects, this Quick-Play Spell is your best bet.
Chain Fog Control to Enemy Controller, Paleozoic Canadia or whatever else to get some value out of the monster that was targeted or just use this with Double Summon to get even more counters on the monster you need.
This Continuous Trap Card, that you might have used for farming purposes, synergizes very well with Cloudians: the monsters can be destroyed by battle and Spirit Barrier prevents you from taking battle damage as long as you control a monster.
A card that would have a similar purpose in this deck would be The Sanctuary in the Sky, which can also be searched by Zeradias, Herald of Heaven; the point is still not taking damage despite the fact that your monsters usually don’t go over 1500 ATK.
Activate Spirit Barrier right away when the opponent summons Recon, Scout Fur Hire to prevent it from destroying it or simply summoning a Wiz and negate its activation.
The main idea behind this would be to try and make up for the naturally low stats that Cloudian monsters have, but, even with that 500 ATK boost, they are not that impressive.
Umiiruka allows you to finish off the opponent faster; it would take at least two turns of direct attacks with a full board otherwise.
This Skill can increase the ATK of all your monsters by 100 for each monster on your side of the field, meaning it will give a maximum of 300 ATK to each of your Cloudians: it’s not exactly impactful, but it’s still a decent option.
Since Cloudians are Fairy-Type monster, this Skill can function decently paired with this deck: you gain 1000 Life Points each time you draw a Fairy-Type monster during your Draw Phase after you reveal that card.
Gaining Life Points is unfortunately not really that crucial for this deck, so it’s a suboptimal option.
It's encouraging to know that the main way a Fur Hire player has to get rid of a Cloudian monster is either with Donpa, Marksman Fur Hire or with Treacherous Trap Hole; after Donpa will join Enemy Controller in the Semi-Limited List, it's safe to say that nobody will run the Quick-Play Spell that would have been able to cause your monsters to self-destruct.
The Monster Card Zones are very limiting for Fur Hires and, unless they start tributing their monsters, once their part of the field is full, there's not much else they can do: they won't be able to activate their effects that trigger when another Fur Hire monster is Special Summoned.
Spirit Barrier, if it's not negated by Wiz, has the potential of locking your opponent temporarily; set up your Fog Counters and then start to activate your monsters’ effects.
It's safe to say that, starting from August 29, Amazoness decks will be even more popular, so it's not encouraging that the main thing Cloudians have going for them, protection from destruction by battle, is pretty much useless when Amazoness Onslaught is on the field.
Acid Cloud is very important in this matchup as it can destroy Spell/Trap Cards with its effect, but setting up Fog Counters can be a pretty slow process if you don't have Double Summon or Summon Cloud and you have to keep in mind that your opponent could still just flip your monsters face-down with Paleozoic Canadia or Floodgate Trap Hole to prevent you from activating their effects.
Treacherous Trap Hole and Cosmic Cyclone (Silent as WATER Version) are going to do most of the work here; once Onslaught leaves the field, Amazoness players will likely have no way of getting rid of your monsters aside from Treacherous Trap Hole.
Spellbook of Fate and Treacherous Trap Hole are the main cards you should be worried about: the 3500 ATK Silent Magician LV8 is really not a problem of Spirit Barrier is on the field and it's actually easier to deal with than the Level 4 version of the monster.
Silent Magician can negate Double Summon, Summon Cloud and Fog Control, but the deck has to rely on Fate and Treacherous in order to get rid of your monsters.
So far so good, but you have to consider that Masked HERO decks usually feature Cosmic Cyclone and Treacherous Trap Hole; with only 4000 and monsters with such low ATK stats, you can't play around that much.