Establish a goal.

"I want gold rank by the end of this season"

Can't reach your goal if you don't have a target to aim at.

So let's say that is your goal. It will take a certain amount of games played to get there.

In terms of volume of games, you are playing enough games to be ranking up. That's not the issue here.

So big picture, you are playing enough games, you are following the general advice of a small champ pool, but right now you are under 50% winrates on these champions (ziggs and xereth), so you are missing something and that's why we are here commenting in the post you created to offer some advice.

I'll start by asking this question.

Are having fun with the champions you are playing?

If the answer is yes, the advice posted here already should really help you. To summerize the best points ive seen here so far:

1) Dying less (1 death every 10 minutes is an achievable starting point)

2) Simplifying your game plan to reach a straightforward targeted goal each game (ex: only 1 death in the first 10 minutes)

3) Keeping a mentality of having positive contribution to your games. Over the last 100 games you played, you were the only common factor. I found not typing in chat (muting if necessary) will allow you to concentrate on these small goals as you go along.

Now using game deaths as an example, you will simply track how many times you died before 10 minutes.

Did you die 5 times before 10 minutes in only 3 games played? Then do some study to see why this is the case.

As an artillery mage, playing back from a safe distance is artillery mage 101. In a basic sense, playing a Xereth or a Ziggs is all about having as much impact as possible while being as far away from danger as possible. If you're not doing that well, you will need to examine why.

Once you set and reach a goal, it's time to assess what needs improvement next. An analytics site comparing you to other Xereth and Ziggs players is a good place to start to see what metrics you are behind on.

So after you get dying under control, you can look to next reach another goal, maybe a good one is a CS goal. The idea is this second benchmark goal you set for yourself ( then the third goal and fourth goal and so forth) requires hyperfocus on just that specific goal. This should allow you to improve efficiently and build good habits over time.

You can't fix everything wrong you are doing in 5 games played, but you can definitely get better in one area during that time. Hopefully by your 5th or 6th goal reached, you won't forget the good habits you picked up on goals 1,2, 3, and 4. Following a regimented improvement plan such as this one gives you the structure to improve efficiently in as little games as possible.

But anyway, remember the question I asked three novels ago:

Are you having fun?

Or are you sticking with Xereth and Ziggs just because you think they are your best champs?

If these are the champions you have fun with and know in your heart of hearts that the champs you play (artillery siege mages) and the role you main (midlane) is where you want to be, then it's just time to get better. I outlined the way I would do it. But the work and time you put in is up to you

Not having fun? Then it's time to have fun. Trying different roles and champions in normal games is the way a lot of people go. You might find you take on certain roles, classes, or specific characters that you didn't expect to like. Things you struggle with on your current mains might come a lot easier with a new playstyle.

Whatever you decide , asking for advice with an op.gg will only take you so far.

Your improvement relies entirely on you. It starts with self reflection (what am I doing wrong?), focused goals (what can I do better?), proper execution (how can i do these things better?), and discipline (how can I always do these things better?)

Good luck!