AWS Lambda is an extremely versatile and useful service for both AWS users and attackers alike. There are many possibilities for we can use Lambda to our benefit as attackers, and one of the best things is that our target doesn't even necessarily need to be using Lambda themselves for it to benefit us.
Due to the many different use cases for Lambda, it is always one of the more high-priority services to check out, as it can often yield very fruitful attack paths to allow us to gain further access to an AWS environment. Another thing to keep in mind is that with many services, including Lambda, they are constantly evolving, opening and closing different attack paths that we can make use of; it is important to stay up to date and knowledgeable, because the accounts we are attacking will be making use of those changes, as well.