Mausritter SRD · 2.3.1
Attribute score loss and death
How to play > Combat > Attribute score loss and death
If a creature has their STR reduced to zero, they are dead. If DEX is reduced to zero, they are unable to move. If WIL is reduced to zero, they are reduced to insensibility.
When your mouse dies, roll up a new one. The GM should introduce them as soon as possible. Getting back into the game quickly is more important than realism.