The fact that a Dungeons & Dragons wizard can conjure a magical grenade-like explosion with a fireball spell may be impressive to some, but more remarkable is the fact that every caster can calculate the perfect spot to aim their spells during the chaotic heat of battle, exhibiting superhuman geometry skills and spatial awareness. Rounds are six seconds long in the current 5e DnD rules, and during that brief span of time multiple combatants move and exchange blows. A spell casting character can typically move their speed and cast a spell with a casting time of one action (or sometimes multiple spells, though only one of those can be a non-cantrip spell). Players and enemy spell casters alike tend to select the perfect spot to center their spells to hit the maximum number of enemies and avoid striking allies with area of effect spells.
There is a reason why DnD spellcasters benefit from the Crossbow Expert feat, as it allows them to cast ranged attack spells without suffering disadvantage on their attack rolls while engaged in melee with a foe. Though that aids with spells like scorching ray that involve a single target, many iconic DnD spells like fireball and cloudkill have areas of effect. DMs routinely see player character wizards counting squares to select the optimal origin point for areas of effect. The casual measurement taking place on a map in real life represents a wizard who can estimate such distances perfectly, while moving and avoiding attacks to the best of their ability, all while their allies and opponents are also moving and striking.
Dungeons & Dragons Spells Can Harm Allies Unless The Caster Aims Perfectly Every Time
The absurd level of on-the-fly calculation exhibited by even low-level casters would put Pythagoras or Euclid to shame. One could argue that it makes sense for sizards to incorporate geometric studies into their education, since wizards are an Intelligence-based class. A Dungeons & Dragons wizard could have a backstory where spatial recognition and rapid geometric calculations were part of their curriculum, along with the skill of maintaining Concentration while performing other actions. The Wisdom-based spellcasters are perhaps as easy to rationalize as the Perception skill leverages Wisdom. Clerics using flame strike or Druids calling forth sunburst could be relying on their innate sensory abilities rather than training.
This still leaves the area of effects cast by Charisma-based casters, like sorcerers, bards, and warlocks, in question, as it's hard to justify aiming a spell based on force of personality. It's very possible for a DM to declare that spell aiming practice is part of the standard training regimen for every spellcasting class. The fiction surrounding these classes tends to focus on studying tomes to master arcane secrets for wizards or engaging in prayer and meditation to grow closer to a deity for a cleric, not on aiming spells. DnD Bards went from weak to overpowered in 5e, acting as full spellcasters, like clerics and wizards. A bardic college would realistically need as much coursework on calculating where to center a hypnotic pattern during battle as it would on music and lore.
Time spent calculating where to center a spell can eat up a lot of session time, and bog down battles severely. Caster players usually want to get the most out of their limited spell slots, however, and to make every round of combat count, since a typical DnD battle might be only three rounds long. It is obviously a fantasy genre convention that allows a wizard to use a bit of bat guano and sulfur, along with spoken words and gestures, to conjure a fireball. While that may seem unbelievable, grenades exist in the real world, but perfectly throwing them at exactly the right spot every six seconds, while moving, stretches credibility even further.
Harsh DMs Can Allow Players Only Six Seconds To Select Spell Locations
There are rules only sadistic Dungeons Masters use in DnD, and giving players six seconds to select their spell’s origin points, with no re-dos allowed, is among them. This harsh house rule certainly adds realism to DnD, but it could make the game less enjoyable. It also puts an uneven burden on caster players, where those playing high-level Dungeons & Dragons fighters have fewer issues selecting the targets for the eight attacks that they make in six seconds when using Action Surge.
