The Crimson Binome
Hero
I'm fairly certain that Batman can hide as a bonus action.I'll be sure to bring that news gently to Batman. He's not going to like hearing it though.
Games are defined by their rules. If the DM applies different rules, then the new rules define the game. This is explicitly a power of the DM.What the DM says overrules anything that the rules say. If I say that the ninja vanishes in a puff of smoke, then that is what happens. If you are using the rules to tell a DM what he cannot do, then I don't think you are using the rules for their intended purpose.
The DM is not the storyteller. The DM is the narrator, the adjudicator, the referee, and the player of all NPCs. The story is just something that kind of happens as a side effect of playing.I'm the DM. I'm the storyteller. I'll be the judge of that.
You can do anything you want at your own table, and the only ones you have to answer to are your players. Whatever bizarre inconsistencies you introduce by doing so are not a reflection of the rule system in question.If it is narratively more exciting to have the bear show up somewhere unexpected, then that bear can do anything that I want it to do, for the purpose of the story. As soon as the players lose sight of it, it could suddenly show up anywhere, despite it's movement speed. Yes, even in the car they just exited.