When taking on the role of DM it is easy to become overloaded as a campaign progresses and players gain new class abilities, spells, and magic items. In light of this it is important for a DM not to give a character, or the party as a whole, an ability that will unbalance the game. Players can take the most simple of abilities and exploit them to gain an advantage that the DM never intended the party to have. As a guide for beginning DMs, here are ten abilities a DM should never give a party. The abilities listed are extra abilities that a player gets via something other than from race or advancing in a class.
10 Teleportation
The ability for even one member of a party, let alone the whole party, to teleport can be game breaking if players decide to start bending the rules a little. Let’s say a member of the party gets a ring of teleportation, but it only teleports the wearer and his/her items. The primary goal of the party might very well change to finding a bag of holding, or some other large extradimensional space that is highly portable. Now the entire party can teleport. At this point the DM might as well give the party a bus that drops them off at the entrance to the dungeon.
9 ESP/Detect Thoughts
A DM that gives this ability to a party should expect to never be able to keep something a secret from the players again. Part of the fun of D&D is the mystery that surrounds the campaign/adventure, and nothing ends that faster than being able to read minds. Detect thoughts is a second level spell, so it’s not overly powerful, but that changes when a character has access to this ability at will without penalty. If a DM wishes to give this ability to a character, at least give it some restrictions. Some possible restrictions are: the player must be holding a certain type of gem for the power to function (which is consumed when used), or allowing the character to use this ability once a week.
8 Raise Dead/Resurrection
Why even have the players fight anything if they have the power to bring back fallen party members whenever they want. The only time a player should have access to this ability is when they have a cleric of sufficient level to cast the spell(s). One of the great aspects of D&D is the finality of past actions and the risks of future actions – there are no save games with D&D. When players don’t fear their character dying it takes a lot of fun out of the game, and makes players have their characters behave in a manner they wouldn’t otherwise.
7 Immunity
A DM should never give a member of the party blanket immunity to a damage type. Examples of immunities this entry is referencing are: fire, electrical, poison, disease, non-magical weapons, and breath weapons. Forgetting that a member of the party is immune to fire is easy considering how much other information a DM must remember. Something like immunity to fire could make the climactic encounter at the end of a dungeon far too easy for the party. A way to tone this down, and make it more manageable for the DM, is to make the immunity more specific; like immunity to the fireball spell instead of just all fire.
6 Detect Magic
This entry is specifically for the ability to detect magic at will. At first this doesn’t seem like too powerful of an ability, but let’s examine some ways a party can exploit this ability. A player with this ability will be able to tell if a monster, item, PC, or NPC has an active spell upon it; this will make it harder for the DM to surprise the party.
This ability will essentially also give the party immunity to most forms of magical traps; a character with this ability will see a magically-trapped chest or door glowing faintly. Some possible restrictions for this ability can be: the ability only works via touch, or the power only works when used under the light of the moon.
5 Flying
The primary reason not to give a character the ability to fly at will is very similar to the reason to never give them the ability to teleport. It will not be too difficult for the party to eventually find a way for that character to carry the entire party somehow. Like teleportation, it will probably be through the use of a portable extradimensional space large enough to fit the party. The campaign just became all destination – no journey. This could also result in the party getting a lot of easy experience by staying out-of-reach from ground-based enemies and striking safely from above.
4 Invisibility
The DM just gave a character the ability to turn invisible at will (or at least numerous times a day). Guess what that player is going to do next with that character? The character, if possible, is going to start taking levels in thief when they get enough experience. Now the DM must deal with the fact that 99% of that character’s attacks will be sneak attacks. Also, the entire party can benefit from this invisibility if needed using the techniques detailed in the flying and teleportation entries. It’s bad enough the invisibility spell is as low-level as it is considering what it does.
3 Time Travel
In D&D player’s actions should at least sometimes have lasting consequences. The ability for the party to travel through time is perhaps the most game-breaking ability on this list. If a character dies they can go back and save him/her. If they get a riddle wrong they can go back and try again.
If a player draws the wrong card in a Deck of Many Things they can go back and prevent it from happening. The next thing a DM knows the party is trying to bring in future versions of themselves to help during a tough fight.
2 Any Natural Spell Casting Ability Above 2nd Level
It’s not uncommon for some races or classes to bestow upon a character a free spell every so often (usually once a day). These should of course be allowed and are just something a DM has to keep in mind. What should not be allowed is a player gaining an ability higher in spell level than 3rd. Daily, or at will use of a spells higher than 3rd level is just too powerful unless the party is so high in level they are fighting ancient dragons for sport. Here are some examples of 4th level spells that can unbalance a campaign: phantasmal killer, dimension door, and freedom of movement. Those are only 4th level examples; it gets exponentially more unbalanced when the spell level gets higher.
1 Playing Outside A Character’s Alignment
This isn’t so much an ability for the characters in the party, but for the players controlling them. A DM should, at the very least, politely remind players when their alignment forbids an action. What a DM should not do is allow the players to ignore their alignment restrictions completely. A paladin should not be able to ignore the fact he just watched the party’s thief violently mug a peasant for a few silver pieces. Players have a tendency to ignore their alignment restrictions; which may be why it plays a diminished role in 5th edition. The DM should discuss this with the players before starting to decide how strict the rules regarding alignment will be. If the players don’t want to strictly role-play their character’s alignment the DM should take that into account. On the other hand, a cleric of Lathander shouldn’t be able to literally get away with murder.