The paranoia here is amazing. You probably regret taking the blue pill and haven't got your COVID-19 vaccine yet because you don't want to be microchipped by Bill Gates.
1) In the manner of "rigging" something, we have to agree that the only person(s) who could "rig" this game would be Blizzard unless every opponent you play has figured out to actively hack Blizzard's games to change the results of a random card generator.
2) If we agree that it's not 1) and Blizzard is the one doing the supposed rigging, how would changing the outcome of a random outcome for specific players be advantageous to them in any way? It isn't. There's no Naralek shift at Blizzard to watch every outcome and decide, you know, I don't like the name Garglespore because it just sounds gross and RandomNinja is awesome sounding so I'm gonna give Garglespore a card that won't help him.
3) It's NOT RIGGED. It's bad luck OR the choice pool is intentionally seeded to produce specific outcomes more often than others. That's not rigging because the intention was to make certain outcomes appear less often than others, not to gain advantage. If they are doing it, it's probably altering the power of the card at 3 cost to not be as powerful as the card at 9 cost in the case of Naralex.
4) Naralex just has bad dreams.
That's not how you calculate probability, the more minions in play the less chances Felmaw hits face. And no, Naralex is not rigged, from 5 dreams available, you get 2 and they can repeat, that's all.
Do you really understand how probability works?
You CAN rig probability.
Let's say there are 3 types of items, A, B, and C. If there is only one of each type, the chances of getting an A is only 1/3.
However, you CAN reduce the chances by adding more B or C items. For example, there is only 1 A, but there are 3 Bs and 3 Cs. The chances of getting A is now only 1/7.
These two RNGs are the same. You CAN rig them in the code. It's actually pretty easy.
In fact, Hearthstone has actually confirmed that they rigged some of the Discover card's RNG, so that they can't Discover itself.
You're not "rigging" the probability. Probability is just the mathematical chance of a resulting outcome based on the possible choices and desired outcome. Rigging implies it's being faked to appear real while it isn't. Changing the probability based on the number of possibilities is still a probability. What you're referring to is changing the individual outcome of each individual card's fixed probability by changing the seed.
Think of it like lottery scratch off tickets. They know exactly how much money the entire batch of tickets makes before it's scratched off. They will sell the all of the tickets for X amount and all of the tickets unscratched will pay out Y amount. That's not rigging probability. It fixes the probability of each winning amount based on what was printed by the original batch, that's the seed.
In the case of a lottery, every time a ticket is drawn, those probabilities technically change because either a winner or loser was removed from the seed. In the case of Hearthstone outcomes the seed doesn't change after a card is drawn. So whether it's 1 in 5 because there's only 1 of each card seeded or the seed is card 1 has 2 while cards 2-5 only have 1 each, that makes card 1's probability 1 out of 3 while the other cards are 1 out of 6.
It's also possible that they have different seeds for each choice of a discover where you may have a better chance for holy cards in the first choice, better chance for shadow cards in the second choice and an equal chance for both in the third choice. It's completely based on the seed. You can alter the seed so it doesn't self replicate or include more search cards, etc.
Paladin has strengths and weaknesses just like any of the current meta and has counters just like any meta. You can't simply say, "I play mage and I lose to Paladin all the time and it's unfair!" because your mage deck is probably a bad matchup. That's how metagame works. If you play one deck, another deck is going to dominate you and you will hate it.
Is Paladin good? Of course. Does Paladin beat everything? No way.
If I'm playing Priest and I see a Paladin, I'm not as worried as I am if I am playing Demon Hunter or Warlock. Honestly, you can break it down on every class and every single one of them has at least some success against another deck in the meta. Except Shaman. Shaman is dreadful.
Nerfs don't have to crush cards. Sometimes it's subtle changes that actually are the most impactful.
+1 mana to RSW and Hysteria is important. Both are very big momentum swings and delaying them could lessen them to some extent. RSW specifically also makes the absence of an early Incanter's Flow felt a bit more heavily. It's about slowing down the momentum gain for these decks, Priest in to just having a hand full of dominant answers by being ultra efficient with every spell it plays or Mage cruising through it's deck to yearning for the burning.
The change on Crabrider is actually better than a 1/3 nerf. It makes it a slightly more useful play out of rush themes and less of a late game beat stick. Taking it out of late game Paladin's hands with an 8/8 buff that has to wait a turn to hit face twice is not something that should be overlooked.
Mankrik nerf is largely low impact.
First Day of School change(kind of both a nerf and buff) still gives Paladins the board presence it desires but makes it less deadly on first play of the game. It won't change how much it sees play, it will only change how fast salty people concede.
The buffs were by and large non-factors to the metagame. They may have a minor impact on duels? Shaman fans wanted to make an impact and they may still fail to make a dent in the metagame.
The problem with half of these posts is they are all about "my favorite class needs X buffed", not what need to be buffed to balance the game.
Ideal balance is that all decks are 50/50 win/loss rate but that's a ridiculous dream as both luck and player are determining factors in the outcome of a game. You can't balance all cards to be equal decks to have a 50/50 win/loss rate. So instead you design for competitive balance which gives the class/archetype a fighting chance to succeed. Looking at individual cards is pointless for buffs as it doesn't solve anything directly. For instance, "caravans" are not fixing an archetype, they're just slow and provide no immediate impact.
When an archetype suffers from a specific deficiency and therefore loses more often than it should based on the available card power in the meta, it should be buffed. Consider Shaman in standard which suffers from many such deficiencies. Shaman suffers mainly from clunky mechanics and that their best non-legendary card draw is shared with other classes. Mana Tide gives you a card AFTER your turn is over so you can't even use it until a turn after it was played. Elemental mechanics are just bad design relying on the turn before to activate primary effects. Now add that their "board clear", which does half the damage and costs 1 more than Flame Strike, double the cost of Hellfire and hits your own minions isn't really effective. Murlocs, well, they're not good enough yet and that's ok. Not everything has to be good. more sets can support murlocs down the road.
Possible fixes I see:
Mana Tide Totem: Original text + The first time each turn you summon a totem, draw a card.
All elementals: Substitute "If you played an elemental last turn" with "If you control another Elemental"
Tidal Wave: 7 cost. Lifesteal: Deals 3 damage to all non-Elemental minions. Overload (2). If you control an Elemental, no Overload.
This gives meaningful card draw for totems based on hero power without it spiraling out of control by limiting to once per turn. Removes clunky Elemental mechanics making them straight forward and friendlier to build momentum from. The Tidal Wave card is reduced cost but adds overload like overload does, but rewards an elemental theme.