Super House of Dead Ninjas and more will be delisted, 80% off now

Are you dumb? Super_House_of_Dead_Ninjas is a great game

Looks like it. They didn't released game 4 years already. Warner Bros is probably closing this division.

SHODN made an announcement that Adult Swim is no longer able to continue as publisher:

https://store.steampowered.com/news/app/224820/view/4225021101208248790

No more information than that. They either don't want to or can't tell more.

by a diff publisher? i hope they made an announcement to confirm this before summer sale ends!

While they say it's just "new name", it's actually separate company, so there could be legal issues why it can't be done.

https://find-and-update.company-information.service.gov.uk/company/10015841
https://find-and-update.company-information.service.gov.uk/company/07276983

I'm waffling on it myself. I think we'd probably enjoy it, because we've been enjoying 10 Second Ninja. Also, it looks to have a level builder option or something (I think?) and my son loves doing that.

As for the DLC, one of the commenters on the DLC reviews said it's best for dedicated speedrunners, as many of the add on weapons are bad for boss battles, and only improve your speed by teensy amounts. I think if I did get it, I'd probably just go for the base game, which is pretty darned cheap, even if it's not at it's lowest price.

but knowing that it was on a deeper discount

0.7€ difference, and it costs a whopping 1.39€ now. At this point it's not the matter of money as not the current price is criticized, but the matter of "do I even want this".
Also, historical price is from 7 years ago. It's going to school now, time to move on and not live in the past :D

Humble Jumbo Bundle 12 in 2018, perhaps

For some the devs took over publishing rights, for some (Samurai Jack among others) we don't know yet. Since ASG announced these delistings, we can hope that the transfer of rights is still being evaluated for others.