What are the important tools for a successful marketing strategy that is called for a successful marketing manager?

Marketing strategy involves careful scanning of the internal and external environments. Internal environmental factors include the marketing mix and marketing mix modeling, plus performance analysis and strategic constraints. External environmental factors include customer analysis, competitor analysis, target market analysis, as well as evaluation of any elements of the technological, economic, cultural or political/legal environment likely to impact success. A key component of marketing strategy is often to keep marketing in line with a company's overarching mission statement.Once a thorough environmental scan is complete, a strategic plan can be constructed to identify business alternatives, establish challenging goals, determine the optimal marketing mix to attain these goals, and detail implementation. A final step in developing a marketing strategy is to create a plan to monitor progress and a set of contingencies if problems arise in the implementation of the plan.

the most important tool is Marketing Audit, to ensure understanding of the market

In general there are many... but nothing beats the successful and timely execution of a well prepared marketing plan.