Quick Starter Guide:

At the of the game level up your Flue (starter miscrit) as much as possible alone.

With him you can catch and level other miscrits you get.

Do NOT spend your Platinum early on in the game, you will need a lot of those later on.

Always do you campaign, it is one of the best Platinum incomes early on in the game and even level up some Miscrits, it gives a lot of XP.

Some good PvE Miscrits to look out for early on in the game:

1. Dark Cubsprout

2. Elefauna

3. Blighted Cubsprout

4. Weevern
After you unlock mansion, use Elefauna until then, you can skip this Miscrit if you want.

With one of these 5 Miscrits you can hunt and train others.

At level 50 make sure to pick up Fortune trait in your level Menu, you will need that gold later on.

Best way to Catch and Train new Miscrits:

First the Catching guide:

In this game lower the HP wild Miscrit has, higher the chances to Capture them.
High rarity Miscrits are harder to catch and best way to catch them without wasting Platinum is to bring them really low.

Best way of doing that is to bring maxed out self healing Miscrit that can also use Toxic, from my experience those would be Elefauna and Weevern.

The strategy that I use for hunting is maxed out Weevern and 3 level 1 Miscrits, those 3 Miscrits will drop the level of wild Miscrit you find, making it easier to kill or catch.

When you find a Miscrit you want to capture, hit them with a weaker move and drop them to around 31-38 HP, after that use Toxic that will do 30 fixed damage over 3 turns and with Weevern spam Rejuvenate (+20 HP healing move that has no cooldown) or Pollen with Elefauna.
You can also start doing this if the Miscrit has 61 or 71 hp, use toxic and reset it, what matters it that it has 3 stacks at around 31+ hp.
This way you are making sure not to kill the wild Miscrit but also drop it to the lowest HP possible while staying at full HP.

Make sure to catch all S+ Miscrits even if duplicates, you will need those for Breeding later on.
Also catch A+ Commons that have Green HP in stats in case they have RED SPEED, really needed later on in Breeding.

Leveling your Miscrits guide:

For this method Self healing Miscrits are the best once again or anything that can 1 shot wild Miscrits in that area.

Going to stronger areas can be a good way to level up but going to slightly weaker spots where you can 1 shot wild Miscrits with you carry is more XP per hour.
Best Miscrits for this Strategy are mostly any high AP Miscrits with relics that you have, best in slot by far is Blighted Cubsprout (in case he is not nerfed after I make this guide).

You can use 3 level 1 Miscrits like shown in the picture if you are just hunting, or up to 3 Miscrits that you want to level up.

Quick Breeding Guide:

Some tips to get S+ or A+ Red speed Miscrits much easier.

Breeding can be looked at 1/3 or 33% chance on EVERYTHING.
Both the Miscrits you put and the color of their stats.
For example if you put 3 Miscrits that have Green HP the outcome will 100% be Green HP, and that is how it works for all stats.

Generally you want at least 66% on Miscrit and stat outcome for higher odds but it is always a gamble after all.

Best way to get S+:

Put in 2 any rating (Higher is better) of the Miscrit that you want S+ and 1 S+ Duplicate that you have (This is why having multiple S+ common duplicates comes in handy).
This way you have 66% to get the Miscrit that you want, 100% on most stats to be Green and 66% on up to 2 stats. Best odds for S+ but remember, still a gamble xd.
You can also try 1 high rarity Miscrit and 2 S+ common fillers but odds are lower that you will get your desired Miscrit.

Best way to get A+ Red Speed Miscrit for PvP:

If you have follow the previous guide, you probably have some A+ or maybe even A Red Speed common duplicates, best way to get Red Speed on higher rarity Miscrits is to use 1 of those at either S+ or S White Speed and 2 Red Speed commons and hope for that 33% to land.
Getting Red Speed naturally on higher rarity Miscrits is much much harder.

In case you already have higher rarity Miscrit with Red Speed and other White/Red Stats best way is to use that, S+ version of it and 1 Red Speed common.
This way you have 66% chance for your desired Miscrit, 66% chance for Red Speed and almost 100% chance for everything else to be Green. Best possible odds ever.