A shield takes 1 action to equip (PHB 146). I'm an new DM and would like to allow that in the first round of battle the PC may use the "interact with objects" time (PHB 190) to equip its shield, if not already equipped.
Reason I want to allow this is that I don't like the PC to always have its shield up, just in case there's going to be a battle.
Perhaps I'm overthinking this, but could there be any reason I might consider to not have this house rule?
EDIT: Based on the helpful feedback here, I've written this house rule as follows (and all house rules are discussed with the party before the campaign starts):
Provided that you are proficient with shields, you may equip your
shield as an "interact with object" move (only) at the beginning of
a battle. This house rule is not valid:
- When you have explicitly declared that you either have equipped or unequipped your shield.
- When you are surprised in your sleep.
- When you have your shield stowed and cannot reasonably have it ready at a moments notice.
At the DM's discretion (and with reasoning) this rule is unavailable or requires an acrobatics check.
Example: A surprise attack in a location where you could not reasonably have expected this.Rationale for this rule: Prevent micromanagement of player state.
Best Answer
It devalues "social combat" tactical decisions.
The decision to wield a shield or not has in-game consequences, from both combat and social interaction perspectives.
Mechanically, shields offer a +2 AC bonus (a significant boost in D&D 5E's bounded accuracy system) and require an action to don/doff (a premium resource in the action economy).
A wielded shield indicates that the bearer is expecting a fight. This probably wouldn't raise any eyebrows if you bumped into a merry band of adventurers running around the wilderness or dungeon, but it has a different social context in more civilised locations. Shopkeepers, tavern owners, and city guards may be rightly concerned to see a group of armed mercenaries roll up like they're spoiling for a fight.
The decision to remove shields is a tactical one. Does the party want to try to pass through peacefully, but potentially leave themselves more defensibly vulnerable if a fight arose? Or are they willing to potentially create conflict in order to maintain their defensive capabilities?
Being able to efficiently don a shield with an object interaction undermines this social combat. With this Homebrew rule, you give the PCs the ability to circumvent these social combat scenarios and still maintain combat readiness. This rule removes that decision making and could produce less interesting scenarios as a result.