This environmental diversity and the civilisational co-dependence it implied and intermingling it encouraged had been Tier’s raison d’être, the very foundation of its purpose and fame for the seven thousand years it had existed. Its original builders were, perhaps, unknown; they were believed to have Sublimed shortly after building it, leaving behind a species - or model, depending how you defined these things - of biomechanical sintricate which ran and maintained the place, were individually dull but collectively highly intelligent, took the shape of a small sphere covered with long articulated spines, were between half a metre and two metres in size and had seemed to have an intense suspicion of anything possessing less of a biological basis than they did themselves. Drones and other AIs were tolerated on Tier but very closely watched, followed everywhere and their every communication and even thought monitored. Minds were immune to this sort of treatment of course, but their avatars tended to attract a degree of intense physical observation which bordered on harassment, and so they rarely bothered entering the world itself, sticking to the outer docks where they were made perfectly welcome and afforded every hospitality. Tier, after all, was a statement, a treasure, a symbol, and as such any small discriminatory foibles it chose to display were considered perfectly tolerable.

The ysner-mistretl race track was one level up from the tier where the Homomdan mission was housed and three levels down from Leffid’s home circumference.

‘Leffid,’ the vice consul said. He was a rotund, massy male of apparently indeterminate species, vaguely human in shape but with a triangular head and an eye at each corner. His skin was bright red; the flowing robes he wore were a vivid but gradually shifting shade of blue. He turned his head slightly so that two of his eyes regarded Leffid while the third continued to watch the race. ‘Did I see you at the Homomdan do last night? I can’t remember.’

‘Briefly,’ Leffid said. ‘I waved Hello but you were busy with the Ashpartzi delegate.’

Vice-consul Lellius wheezed with laughter. ‘Trying to hold the blighter down. It was having buoyancy problems inside its new suit; automatics weren’t really up to the job with the AI removed. Terrible thing when one of these gas-giant floater beasties suffers from flatulence, you know.’

Leffid recalled that Lellius had rather looked as though he’d been wrestling with the bow-rope for what appeared to be a small airship at the Homomdan ambassador’s party. ‘Not as terrible as it must be for the inhabitant of the suit, I’d guess.’

‘Ha, indeed,’ Lellius chuckled, nodding and wheezing. ‘May I order you some refreshment?’

‘No, thank you.’