Steam Summer Sale

If you wanna 80-85% go back in time to 2011-2013 :)

I'm level 8 by now, took me about 8 hours of manual grinding. Reaching level 9 will take me more than twice as much exp as to get to level 8 and hard levels are already done on my planet by now which makes it even more of a grind. :( (focussing on the art one due to Hollow Knight)
As soon as you reach level 7 and get the black hole hard levels are a joke. You basically keep your enemies stuck in the hole and throw the bombs that you unlocked at level 5.

After you reach level 9 it is claimed the EXP to reach level 10 is equivalent to playing the highest threat square for about 20 hours. Like a few years ago reaching maxing that badge out is going to require auto playing scripts if you're into that. There are several of these already and the game is coded far worse than the one a few years ago. For example, you can kill all enemies on spawn by entering the following into your console:
CEnemy.prototype.Walk = function(){this.Die(true);};

Wow only 100? there is like millions of steam users. Why they don't just give it to whoever joins the game or at least reach a certain level maybe.

Same, although some SG'ers did win during that Game Award stream (not me).
It is somewhat spread by players needing to select one of 4 giveways with 400 copies, some wont do the game etc. but it's still fairly unlikely :/

How do I get Summer Sale trading cards?
Summer Sale trading cards are only available during the Summer Salien Event. There are six ways to get them:
Play the Salien Game
You can earn up to three trading cards each day by playing the Summer Salien game. Have fun and earn some rewards while you're at it!
Craft a Game Badge
Crafting a badge for any game during the sale will get you an additional Summer Sale trading card.
Make a Purchase
As an extra reward for purchasing, for every $10 USD spent during the sale, you’ll receive a Summer Sale trading card. From your Summer Sale badge page select
Go through your Discovery Queue
If you’re Steam Level 5 and above, you’ll get a Steam Summer Sale trading card once you view all the items in your daily Steam Discovery Queue. You can continue and go through your Discovery Queue two more times each day to get a maximum of three card drops each day. (If you reach Steam Level 5 before the end of the sale, you’ll be granted the cards you earned by exploring your Steam Discovery Queue during the sale).
Trade for them
That’s why they’re called trading cards! Find friends with other cards and make trades. Your summer sale badge page shows which friends have the cards you need.
Buy them from the Community Market
Sell the cards you don’t need and buy the ones you do, all with other Community members. Turn those duplicate cards into Steam Wallet funds to buy games.
View the Community Market

All in the FAQ

During sale?

And the Summer Sale badge itself gives emoticon,background and a salien cosmetic item (which albeit 0,03 due to overstock is more than most sales give you)

(someone replied to you without hitting reply, check the topic and the post below yours)

Yeah, DLC seems to stay costly, mostly around 50% off. Of course DLC or games I stick to my rule of 75% or bust, maybe excepting things that can't get lower percentages due to Steam's lower limit of 39 cents.

In your opinion, what would you consider as low price already? I'm split between getting BD2 vault upgrade 2 (raise cap to 73) or not

Random errors are an essential part of all Steam sales. Other than using a script to play it like everyone else to not break your wrists, you should just wait a while and try again.

Yes

why u asking? on every prev sales people craft 100 and even 1000 lvls
is any limits of crafting on current sale?

At least 3 users have the rank 5 badge now. It's on level 16.

Someone has reached level 20 (don't ask me how it's possible), and he's still at rank 5. Which means there are more than 20 levels.

It's on the front page (July 5th).