This white paper discusses the implications of Web3's smart contracts on blockchain transactions and the resulting security challenges. It outlines how traditional cryptocurrency transactions have evolved with the introduction of smart contracts, which allow for more complex interactions but also create new vulnerabilities. The paper details the concept of Transaction Simulation, a method that enables users to evaluate potential transaction outcomes without executing them on the blockchain. By simulating transactions, users can better understand the expected results before approval, thus mitigating risks associated with malicious Dapps. However, the paper also addresses the limitations of current Transaction Simulation solutions, including event dependency issues and potential exploits by attackers. Furthermore, it suggests that while Transaction Simulation is a valuable tool, it should not be viewed as a comprehensive solution and must be complemented by other security measures to ensure user protection in the evolving Web3 landscape.