The Maximally Greedy Action Plan is a concept in the Game Theory, It normally happens in the extensive-form bargaining games.
Suppose we are in a pie-divided game, there are players, and the Maximally Greedy Action Plan means that, when player is making proposal, he would only propose , and he would reject all the proposals made by player .
The Maximally Greedy Action Plan has some properties, for example, we can prove that, any action plan is a Best Response against the Maximally Greedy Action Plan, such that any action plan is Rationalizable.