In Germany, if you're stealing, EVERYONE have a right to take you down (WITH VIOLENCE). I'm moving to Germany 🇩🇪📍

Deadly self-defense is legal in Germany. The self-defense law (in particular Sect. 32 of the Criminal Code) makes no restrictions as far as the type of aggression and the type of defense is concerned. That means that - in principle - you can defend yourself against an attack by any means that is necessary to stop it. The principle behind that is "das Recht muss dem Unrecht nicht weichen", which translates to "the law does not have to yield to the unlawful". That particularily means that:

You do not have to run.
You do not have to yield.
You do not have to wait for help from public authorities (notably the police).
You can defend yourself (against any attack on you, be it life, limb or property), no matter if that would mean commiting a crime (even if that crime is killing a person). This is called "Trutzwehr" or "schneidiges Notwehrrecht", which can be translated to "active defense" or "aggressive defense" as opposed to passive defense.


However :

Attackers that clearly can not understand the severity of their actions have to be spared from extreme effects of your self-defense. The classical book case is that you can't shoot little children stealing apples from your tree (DAMMIT! I wanted them apples 🍎🍏).
If there is a massive discrepancy between what you want protect and the damage the attacker has to endure (called "qualitativer Notwehrexzess" - translating to "qualitatively eccessive self-defense". If someone insults you, shooting him might go to far, since while your honour is attacked (which is protected by Sect. 185 Criminal Code), the attacker's life (protected by Sect. 212 Criminal Code) by far outweighs it. Note that, to ensure the effectiveness of the self-defense laws, the discrepancy must be extreme. And it does not mean you can't defend yourself. You just have to choose a less severe measure. So you might get away with knocking the insulter out.
After the attack is over you hit the attacker once too often, which causes his death (called "quantitativer Notwehrexzess" - "quantitatively eccessive self-defense". The attack was over at the time of the deadly blow, so your right for self-defense had ended. You might get away without punishment, if it was impossible for you to realize that the attack was over.
If you only think an attack is happening, but it is not (for example someone attacking you with a rubber knife on Halloween). In this case there is no attack and so technically there is no right for self defense (called "Putativnotwehr". Similar to the cases of excessive self-defense, it depends on your individual case (notable if you had a chance to realize the attack was false) if you are punished or not.

To sum it up: You have the right to defend yourself by any means necessary, but you are held responsible if you go to far (not just a little, but really really to far).