Everyone likes mush. It gets you things. As someone who has a lot of mush, here are some tips I personally use to make mush. Some of these might be obvious, but I'm just putting them out there.
I have other tips, but I have too many so here are like four for now
1. Go exploring.
I don't buy a bunch of explore moves and use them all at once, so I don't know how well that works. The way I explore for mush might be a little weird, but it works out for me.
I buy one Chinese Pottery at a time, but after I buy it, I keep that tab open without going anywhere to see how many mush I have since I've bought it. I have two other tabs open: one for exploring and the other one to check up on how much mush I've gotten from explore. Every time I make more mush than what I have from the Chinese Pottery tab, I buy another one from that tab and keep going.
This is a good way to train wolves without feeling you're losing too much because you have the amount of mush you have right there. I don't know. It works for me, so it might work for someone else.
2. Sell your stuff.
Appraise EVERYTHING to Montak and sell it to him.
Craft the "useless" things like bead necklaces, appraise it, and sell it to him. Go to barter and buy the one or two missing pieces cheap (~5 mush). Realm > Barter > Search > Lowest to highest order.
Use your market den. Sell things based on how much other people sell them for. (Honestly I just sell them for however much I want lol)
3. Invest in good battle wolves.
Battle wolves get me most of my mush on here. Even if a wolf is very expensive because of the CP it has, it will be very worth it. For example, my wolf Dreaming of Florence costed 694 (yeah I know), but if you add up the math from what he's killed, he more than made up for it.
Get people to put CP on your wolves for 10-15 mush per 5 CP. Advertise it in sales.
4. SAVE.
Use your mushroom hole. I don't use it, but I've heard to put half of what you've earned in it. Be patient.
Spring 
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Flood Moon: 
