Ritual Casting

While casting a ritual spell you must maintain concentration and can take no other action or make any skill check unless you first stop casting. If you are casting a ritual spell when a skill check is required, you automatically fail. If you stop casting or take any action while casting a ritual spell the spell fails, consumable components are consumed, and you will need to start over from the beginning.

Ritual Casting - PHB pg. 203:

“…When you cast a spell with a casting time longer than a single action or reaction, you must spend your action each turn casting the spell, and you must maintain your concentration while you do so…”

 

DM Ruling

  This means that you are totally focused on casting the spell. It does not mean you can’t walk but it does require others to guide you while you do walk. If you choose to walk while casting the spell you cannot do anything that requires an action such as a skill check (perception, investigation, athletics, acrobatics, history etc.) If you come across something while casting the ritual spell that requires a check either the check automatically fails or one of your party members gets your attention for you to do this action and you fail to cast the spell and have to start all over again. I’d go further to say that while you may be hearing most of what is going on, your ability to interact with others will be extremely limited while you’re casting a ritual spell. A few short responses are okay but if you engage in debate the ritual spell will fail and you’ll need to start over again.

Casting a ritual spell while walking in a dangerous environment is inherently dangerous. It’s safer to have everyone wait for you to finish the spell. If the party wants to move on and you want to cast a ritual spell, either the party needs to stop and wait 10 minutes every time you cast a spell or you will automatically fail any challenges you may come across while casting the spell.

Ritual spells could be cast constantly but that means the party is stopping every time you wish to do so and that may not be reasonable. Use them when they make sense and the party is willing to wait for you.