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Suppose that Bob is mounted on a warhorse (speed 60'). Is it correct that the character and warhorse get separate sets of actions? Thus, Bob could have the warhorse take the Dash action (so it gets a total of 120' of movement) then move 120' on the warhorse, and Bob could still attack with his own action?
Do you have to have the warhorse take its whole turn and then Bob take his whole turn, or can this be interleaved? For instance, could you have the horse move 40', then Bob takes his action, then the horse moves 80' more? Or would you need to use readied actions to set something like this up?
If the warhorse and Bob do have to take their turns separately, do they have to take them in the same order each round? For instance, could the following happen: round 1, the warhorse moves in and Bob makes a melee attack; round 2, Bob makes a melee attack and then the horse retreats?