Arcane portal dais

Octagonal dais 14.4 m across on three 19 cm steps all round, its top 12 m across paved with a glowing ring inlay; the portal arch stands at its centre (place_arch) with room to fight in front of it. Rune-cut grey stone ringed by floating crystal shards, a violet swirling portal.

13.30 × 13.30 × 0.79 m