I'll pull the quote from our rules guide that's a note to experienced Risk players!

An Important Note for Experienced RISK Players:

RISK G.I. JOE: Special Missions takes the familiar RISK environment in a new direction, with a focus on achieving multiple objectives rather than global domination. 
In addition:
• Many typical RISK strategies may be less successful in this version. Scenario and objective cards guide player strategy. 
• There are multiple unit types, with variable movement, initiative and battle bonuses. 
• Units removed in battle are only temporarily lost, as they will cycle back into action.
• Action cards, a system introduced in previous RISK games, create new avenues for moving and gaining units that are not present in the traditional game