Imagine if a doorway could transport you to another world - Portal magic amplifies doorways' inherent ability to carry one to new places.

Concentration
To maintain a spell, you must maintain concentration on it.

Magical Focus
Portal magic requires a focus: Doorways, windows, standing stone archways, or drawn circles all provide a focus upon which a magic portal can be opened.

Touch
You must touch the place where the portal is opened. (w/ perks: Line of sight, arbitrary)

Action
Opening a portal requires an Action.

Portal
As an action, you create a magical portal. By touching a door, window, or representation of a door, a 1 meterThe portal must be placed inside a physical passageway such as a doorway, window, or mirror, or placed in a representation of a door, such as a picture of a door drawn in chalk, and you must be able to see the portal. The portal occupies the space of the door or representation upon which it was cast, and appears as a shining surface. If the caster chooses, the destination beyond the portal can be visible or hidden behind this surface. The portal remains active as long as the caster concentrates on it.¹⁾ The range at which a portal can be opened increases as the character gains ranks in Portal Magic. You can close any of your own portals at any time, though their closing may be hindered by objects in the way, and creatures that are caught can usually climb out without the closing door hindering them doing so. You may have up to two portals open at a time, opening a third closes the first. Closing another's portal requires an action, and requires a roll check if the portal is of equal or greater rank than your own in Portal Magic.

Portals that open on each other are called 'linked' or 'paired'. Paired portals can be traversed instantly, as if they occupied the same space.

• Portals, Rank 1: Your portals can be placed up to 3 meters from you. Your pocket dimension is 1 cubic meter in volume.
• Portals, Rank 2: Your portals can be placed up to 7 m from you. Your pocket dimension grows to 8 cu m in volume.
• Portals, Rank 3: Your portals can be placed up to 20 m from you. Your pocket dimension grows to 125 cu m in volume.
• Portals, Rank 4: Your portals can be placed up to 80 m from you. Your pocket dimension grows to 1000 cu m in volume.
• Portals, Rank 5: Your portals can be placed up to 400 m from you. Your pocket dimension grows to 8000 cu m in volume.

Each time you gain ranks in Portal Magic, you may also gain your choice of one of the following perks:

Dimensional Anchor
Prerequisite: Portal Magic rank 1.
You cannot be moved, teleported, or traverse portals against your will by magical means. You also gain the ability to draw a dimensional anchor sigil on a person or object that prevents them from being moved, teleported, or traversing portals by magical means. Drawing the sigil requires an action.

Instant Passageway
Prerequisite: Portal Magic rank 1.
You can now open two portals in a single action, rather than having to use two actions to do so.

Knock
Prerequisite: Portal Magic rank 1.
As long as the target is in sight, you can, as an action, telekinetically open or close unlocked doors, lids, latches, windows and such from a distance equal to that which you can open a portal. You can also disengage locks, but doing so takes concentration and time - 1 minute for basic locks, 1 hour for complex locks, and 1 day for locks that are especially advanced or sealed with magic.

Magic Gate
Prerequisite: Portal Magic rank 1.
If you spend time drawing a runed circle known as a Magic Gate, you can create a representation that satisfies the doorway prerequisite for portal magic that can be activated even if it is not within sight. The range at which the Magic Gate can be activated depends on the time spent drawing the Magic Gate, as such: Distance in Miles = Days spent, squared. For example, spending 1 day on Magic Gate, allows that circle to be activated as a magical portal as long as the caster is within 1 mile. Spending 2 days on a Magic Gate allows it to be activated up to 4 miles away. Creating a Magic Gate to traverse the diameter of the Earth takes 90 days. Each pint of sapient blood used in the drawing of the Magic Gate reduces the required time by 1 day to a minimum time of 1 day to draw it. As usual, if the Magic Gate is activated singly, it opens on the caster's pocket dimension. If activated in concert with another portal, it can be traversed.

Multi Portal
Prerequisite: Portal Magic rank 1.
The maximum number of portals that you can have open at a time increases from two to unlimited. If you have more than two portals out, each time a creature enters one portal, you may choose their exit portal.

Portal Grasp
Prerequisite: Portal Magic rank 1.
Closing your portals can now grapple creatures as they attempt to pass through, instead of forcing them to choose one side or the other.

Sealing Sigil
Prerequisite: Portal Magic rank 1.
As an action, you may draw a sealing sigil on a surface. While this sealing sigil is intact, magical portals cannot be opened on the surface; If the surface is a closed door or closed window, or some such device, it cannot be opened. Enough damage to the material upon which the sigil is drawn will destroy the sigil. A sealing sigil can be drawn in chalk as an action, but if more time and better materials are spent to draw the sigil, it may be nearly impossible to destroy.

GM note: ANY PORTAL MAGE can activate a portal runic circle, as long as they've spent at least 1 day reading the runes of the circle. Thus, most portal mages keep their runic circles hidden and secret. If a city or army uses such a circle, they will usually heavily police the use of portal magic, in fear of their shipping lane or army being fatally disrupted. LIFEHACK for smart portal mages: A Stargate, just like the one from the movie or TV series can be created using Sealing Sigil and Magic Gate in concert with each other. The inclusion of Magic Gate is obvious. Sealing Sigil can be creatively used to make a puzzle-box like interface of 'chevrons' just like from the movie. A particular entry of chevrons allows the gate to be locked, unlocked, or even destroyed if the clockworks are so constructed.

GM note: Portal magic can be used for scrying.

GM note: It is reasonable that a portal mage could open a portal using the horizon as the portal's perimeter. Complications: perimeter neither smoothly circular or rectangular, perimeter too far away, opens to pocket dimension, etc

If a portal mage opens a portal inside his pocket dimension:

• IF there are no other portals open, THEN the portal mage chooses one of the two following:
  • Anything entering the portal exits it in the same moment, leading to the same spot in the pocket dimension.
  • The new portal leads outside, as an exit from the pocket dimension.
• IF the new portal is linked to an outside portal, THEN the portal acts as if it was an exit to the pocket dimension.

Order of operations for portal?:

• Action
  • Choose representation for portal.
  • Choose whether portal is linked to another open portal, or unlinked and opens on the pocket dimension.
  • If any other portals are opened to a pocket dimension, they can be instead linked to the portal being opened now.
  • Portal opens.
• Traversal

Possible Bond? Study, demonic contract, faith, (probably none of these, doorway magic feels like a homely magic or a magic found by people who like shortcuts)

Possible Curses? Insanity caused by seeing between dimensions. Splinching. Something coming from the other side. Evil twin. Transporter clone.

perk ideas:

Consider making pocket dimensions accessible via perk, instead of base.
Pocket Dimension
A portal opens the way to a miniature parallel dimension (a “pocket-” or “hallway-dimension”) owned by the caster, or to another portal created by the same caster. The pocket dimension acts a space owned by a particular caster that can only be accessed via that caster's portals. It has a volume of 1 cubic meter at rank 1, and grows as the character gains ranks in Portal Magic. When the portal to the pocket dimension is closed, the portal dimension is a sealed airtight, unlit space. When one is inside the pocket dimension, one can see any active portals linked to it.

ALSO CONSIDER: Pocket Dimension:
The space between your portals is now a large room. This room and its contents persist even when you have no portals open.

Mid-Air Portal / Anchorless Portal / Floating Portal
(would also remove the necessity of drawing a portal? Maybe you still have to mime the action)

Tunnel
Placing a portal on a surface automatically generates a portal on the opposite side. Range limited by ranks. (“…from a distance equal to that which you can open a portal”)