Can someone tell me why matches in Diamond 1 are disproportionately harder than those before them

https://hsreplay.net/replay/38EGqeHG2LBsk5vgk9AMnj

About half of my games at Diamond 1 are like this. I've been bouncing between the bottom of rank 2 and the top of rank 1 for 3 days. Nearly every game is a one sided highroll. I hate this deck but am only playing it out of desperation at a friends recommendation - I was previously playing tempo warrior and miracle druid and got 1 or 2 games away from legend but was forcefed losses. I swear at this point my account has a bad RNG seed or something.

Your opponent has a 5 mana lead on you, and you didnt draw your soul mirror on time. Also you didnt have convincing infiltrator early.

Just bad rng, which is why most decks dont get past 55% win rates in general. This is particularly bad with res priest since their cards are so expensive, and priest cant draw for shit. So you can literally have games where you skip the first 6 turns cause your hands too reactive and expensive.

Just take a break and try again. A general advice is to try climbing with decks you actually like, so you'll play longer and the losses dont feel too bad.

You are playing a deck cause it was recommended. Mistake number one: you are a slave of the win. I get the feeling you are playing it for the wins and you don't like the deck.

Mistake number 2: playing a deck that relies upon what you draw. It's a green cards deck but unlike aggro its a card per turn if u draw them cause u cant even influence that since theres no card draw.

Mistake number 3: wanting to climb with a slow deck. So im assuming u want ro reach legend independently of the pleasure u have in piloting the deck. Ive done this before and normally i just pick an aggro deck. Reason is i dont like the deck i just want to climb quickly so i choose an aggro deck. Result? It steamrolls the low to mid ranks easily but once I reach a high rank i walk into a wall. I think the main issue is since i dont like the deck i just dont put much thought into it and end up losing a lot. Funny thing is with some aggro decks that actually remember liking i didnt hit this wall cause i was making smart plays to avoid certain outcomes and play around removal

The lesson of this 3rd mistake aint "bro just dont play aggro" but it is dont play something u dont like. AND if u are indeed just using a deck for climbing regardless of ur enjoyment than i seriously recommend aggro because its a lot faster. Winning or losing fast makes the climb easier.

U chose a really slow deck to try and climb. Thats quite admirable but ultimately a mistake. The main issue is that u are relying ur climb and success on a deck. The deck doesn't play by itself (tho rez priest archetype are almost that) and thats the main problem. It was recommended so u just go with it regardless.

U are the playing. U are the one trying to reach legend.  Not the deck. Dont make urself a slave of it. And dont make the deck your slave either. You are partners in crime treat it well treat with respect for ur opponent. Predict ur opponents play. Play around the worst possible outcome each turn. Know ur opponents deck know ur own deck and what draws could net u the win play with those odds predict the rng and u will come out on top.

Sadly for that im not seeing a rez priest pulling it. Its a very one sided deck. Very linear deck meaning u either have the cards or u dont. Most decks have differently plays. Easy deck like the demon hunters etc rely on those broken cards but the deck works regardless of what the cards are cause u are making different plays. Rez priest is just did i drew my taunts? Do i have my removal cards. And did I drew my mass rez? The only combo is the infiltrator and grave rune. If u don't get ur cards online when u should u just lose. Also u rely on a meta not using shaman cause the highlander mage is a pain cause they run poly and zephyr can get u one. The fact that shaman and their possibility of discovering hex is off meta makes rez priest more viable. Of course rogue counters priest hard and galakron rogue is still very good.

Tldr: play a good deck but one you actually like or else you will feel like you are on a job. Dont be a slave of the win or you will end up defeated by your own deck not the opponent's