What is the function of the "summon" action in Riftbound?

The "summon" action in Riftbound serves the critical purpose of allowing players to deploy units onto the battlefield. This action is fundamental to gameplay, as it enables players to bring new allies into play, thus enhancing their strategic options during battles. Each summoned unit can have its unique abilities and roles, further influencing the dynamics of confrontations. Strategic deployment of units can turn the tide of battle, whether by strengthening defenses, launching aggressive attacks, or utilizing special abilities.

The other options do not accurately reflect the role of the "summon" action. For instance, initiating a retreat would involve withdrawing from combat rather than bringing new units in. Drawing additional cards pertains to managing strategy and resource allocation but does not involve direct combat participation. Lastly, replenishing energy resources is a different aspect of resource management within the game, not related to summoning within the battlefield context. Understanding the specific role of the summon action is essential for effectively engaging in Riftbound's strategic gameplay.