Animated chair
Animals don't like magi, and horses are certainly not going to let a magus with a blatant gift to ride one of them. It's not suitable for the proud magi to walk with their own feet, if an other possibility does exist.
This is what we do. We take a metallic (probably iron) chair, open it for enchantment. Chairs are large (e.g. skeleton) but not huge (wagons, small rooms), so vis cost is 5 (base metal) x 4 (large) = 20 pawns of Vim. The chair can hold 200 levels of spell effects.
Next we want to make the chair move on its own. Copying the Animate Chair effect from the Enameled Horse (Wizard's Grimoire, p. 110) it is a Rego Terram effect, level 20 (R: Per, Conc, Ind). It's got to be constant use or unlimited with the chair keeping concentration. Constant is probably better (+5). The chair should be pretty fast like this, if the horse can move like "exceptionally well-trained warhorse", it should be quite stable as well.
The rider doesn't want to walk into quicksand or landslide; we need also Eyes of the Treacherous Terrain, Intellégo Terram 20 effect, so the rider can feel safe.
After all this work it would really hurt to see the chair rusting away. Prevent rusting, Creo Terram 20 effect could take care of that. (See Drennus' Bowman, WGre p. 109, and it's Protection from rot -effect)
There are quite a few other enchantments one might want to bestow his chair with. Here are some of them.
| Effect | Arts | Level | Ref. | Notes |
|---|---|---|---|---|
| The Trackless Step | MuTe | 10 | ArM153 | Chair leaves no tracks. Like the spell of same name. |
| Silence of the Steel Step | PeIm | 5 | ArM142 | as per Silence of the Smothered Sound, for stealth missions |
| Jump | ReTe | 10 | ArM128 | as per Gift of the Frog's Legs |
| Fly | ReAu | 20 | ArM121 | as per Wings of the Soaring Wind |
Of course, this would eat up loads of vis and enchanting it would take years. Still, the chair would be remarkable item.