In theory, it is scientifically possible to use gene manipulation technology to give animals synthetic controllable toxic properties. However, there are many technical, ethical and legal challenges to actually achieving this goal. ### Science and Technology Level 1. **Gene Editing Technology**: Currently, gene editing tools such as CRISPR-Cas9 are able to precisely modify the genomes of plants and animals to a certain extent. This provides a technical basis for designing organisms with specific functions. 2. **Toxic Gene Integration**: In theory, specific toxic genes can be integrated into the genome of animals to produce toxic substances in vivo or in vitro. However, how to achieve "controllability" is a huge challenge, involving the fine regulation of gene expression and the spatiotemporal control of toxic products. 3. **Biosafety**: Even if it is technically feasible, how to ensure that the designed animals will not cause harm to the ecosystem or human health in a non-military environment is also a major issue. ### Ethical and Legal Level 1. **Ethical Issues**: Genetically modifying animals to give them toxic properties involves serious animal welfare issues. In addition, the militarization of this technology may trigger widespread ethical controversy. 2. **International regulations**: According to the Biological Weapons Convention, the development, production or stockpiling of biological weapons intended to kill or cause serious harm is prohibited. Endowing animals with controllable toxic properties for military purposes is likely to violate the Convention and other relevant international regulations. 3. **Uncontrollable risks**: Even if there is an intention to control these toxic properties, the unpredictable behavior of genetically engineered organisms may lead to unexpected consequences and increase biosafety risks. ### Conclusion Although genetic manipulation technology may theoretically allow animals to have specific toxic properties, using it for military purposes not only poses huge technical challenges, but also faces severe restrictions and prohibitions at the ethical and legal levels. The international community generally opposes the development and use of biological weapons. Related research and applications should strictly comply with international regulations and consider their potential social and ecological impacts.