Bleed, like most status effects, builds up slowly over time through repeated blows and depletes a huge chunk of your health when it is at its peak. It's a hassle to combat, but it's not something that's Elden Ring Runes supposed to happen in the moment or surprise you. Therefore, the Writheblood Ruins dog's overwhelming capability to instantly bleed is a terrifying anomaly.
In the video above, these strays appear to be infected. The normal attacks they use work just as they should, however for some reason , their combos strike way too many times, as evidenced by the multiple sound effects as well as the rapid bleeding. Even those with maxed-out endurance and vitality stats that govern in addition to damage points to bleeds and health when wearing armor that is heavy duty can't survive for more than a few seconds prior to bleeding into the next.
Based on user comments on Fextralife the wiki site that contains info on Elden Ring as well as other Souls gaming, Writheblood Ruins was at time also the home of an immortal slime, but I'm unable to find any footage of this adversary in the action. It was apparently fixed with the recent 1.03 patch.
Although buy Elden Ring Runes has its fair number of bugs, it is normal for the software. The development process isn't easy even in the best of times. Considering the difficulties of the past several years it's almost a wonder that FromSoftware could launch something that ambitious and still runs pretty well for the vast majority of users. (It's definitely not Cyberpunk 2077). Just sit tight and maybe steer clear of this part of the game for the time being.