Artificer Speciality - Lairtrapper
While many dragons spend their time and spellasting energy on personally laying traps in their layers for would-be invaders and pillagers, it's not unusual for dragons to hire (or otherwise 'convince') mortal spellcasters to do the job for them. These spellcasters often end up following the artificer path of the lairtrapper, those whose magic is based around concealing their spells until the last moment when they can do the most damage. With a careful keen eye for tactics and duplicity, a Lairtrapper is considered priceless to a dragon (or simply a rich person) who wishes to keep their items from coming to harm.
Lairtrappers who end up travelling with adventuring parties often do so in a pursuit of innovation for their craft, if they feel that they have become stale or rote in their performance. Many lairtrappers seek the perfect trap - not one that is perfectly concealed, but one that their enemies willingly walk into, trapped not in body but mind as well.
Tool Proficiency
When you adopt this specialization at 3rd level, you gain proficiency with mason's tools. If you already have this proficiency, you gain proficiency with one other type of artisan's tools of your choice.
Lairtrapper Spells
Starting at 3rd level, you always have certain spells prepared after you reach particular levels in this class, as shown in the table below. These spells count as artificer spells for you, but they don't count against the number of artificer spells you prepare.
| Level | Spells |
|---|---|
| 3rd | Grease, Hideous Laughter |
| 5th | Earthen Grasp, Shatter |
| 9th | Fireball, Glyph of Warding |
| 13th | Banishment, Black Tentacles |
| 17th | Cloudkill, Destructive Wave |
Spelltraps
A lairtrapper's bread and butter is turning arcane power into traps for their draconic masters. From 3rd level when you cast a spell which has a casting time of 1 action, you can choose to encase the spell inside a magical glyph, which lasts until the end of your next long rest. If the spell is of level 1 or higher, the spellslot is expended when you create the glyph. These glyphs are stored on your body as magical tattoos until you choose to place it. Placing a glyph requires your action, and can be done in any square within 30' of you so long as it is on the ground. You may designate the glyph to activate when either a hostile or friendly creature enters the space or starts its turn there. You may also actively trigger the trap by using your bonus action. Only deployed glyphs can be triggered, merely having one on your body is not enough.
When a spelltrap is triggered the spell activates as if it were cast on the creature in that square. Spells that have line or cone effects face the direction you choose, but still affect the square the trap was placed on.
If the spell stored in the trap requires Concentration, then you don't need to provide this until the trap is triggered. If you were already concentrating on a spell when the trap triggers, you must choose which one to continue concentrating on, losing the effect of the other.
Each spelltrap can hold only a single spell, and you can have a number of spelltraps stored on your body equal to your half your intelligence modifier, rounded up. With an innate connection to your spelltraps, you know immediately when one was triggered. You can recover a deployed spelltrap and return it to your body for later deployment by using your action while within 30' of the deployed trap.
Surprise Spell
By reaching 5th level you've learned to enhance your traps further, ensuring that the glyph is more potent. If the spell stored in your trap deals damage it now adds your intelligence modifier to the damage roll.
In addition, your traps are now harder to spot. A creature must beat your passive Arcana score (10 + your Intelligence (Arcana) modifier) with either their passive or active perception in order to spot the spelltrap. If they do not see it, then any attack rolls the spell makes have advantage, and if the spell requires a saving throw, the triggering creature has disadvantage against the initial effect. These apply even if you activate hte spell with your bonus action.
Mobile Traps
Sometimes you need to move a spelltrap that has already been deployed. From 9th level by using your bonus action you may choose one spelltrap within 60' and move it up to 30' in any direction along the ground. As part of the same bonus action you can choose to trigger the spelltrap.
Enhanced Glyph of Warding
From 9th level when you cast the Glyph of Warding spell, the value of the consumed material component is reduced by 10gp multiplied by your Intelligence score, to a minimum of 0gp at 20 intelligence.
Special Spelltrap
Normal spells only go so far, but your spelltrap discoveries take it a step further. At the end of a short or long rest you can choose to make one Special Spelltrap, which lasts until the end of your next short or long rest. A special spelltrap is deployed and recovered in the same manner as a normal spelltrap and does not count against your maximum number of stored spelltraps.
Planar Trap: The triggering creature is affected by the Plane Shift spell, being sent to a randomly determined plane of existence.
Antimagic Trap: When this trap is triggered it creates an Antimagic Field (as the spell) centred on the trap's square for 1 hour, without requiring concentration. Any spelltraps in the antimagic field cannot be triggered while the field is active.
Symbol Trap: Your spelltrap gains the effect of one of the options from the Symbol spell that you choose.
Spellcombination
A trapper needs to be able to take advantage of his creations. From 15th level when a spelltrap or special spelltrap is triggered, you can use your Reaction to cast a Cantrip on the triggering creature.