It starts introducing itself before bringing up anything about the challenge.
It doesn't use language. Just sense impressions. An enormous tower, topped by a brilliant sky-blue light. Back when the sky was blue. Itself, smaller than it is now, watching as the tower collapses and everything is plunged into darkness. Chaos from the collapse, blue flame pouring out and driving off most spirits, but by then it is already old and strong. It doesn't wither. The land settling into its current form, spirits returning or reappearing, thriving. Itself and the few similarly old elementals having uncontested dominion.
This last is represented in its almost-mind by reference to the claim Findekáno just made: ownership isn't a concept it's seen much of before, but the words of practitioners are a comprehensible fact of the universe just as much as the melting point of ice. This is especially true of common and powerful rituals like this one; right now it can handle a lot more than usual of what would look to a practitioner like abstraction. In particular it knows that it gets the first chance to name or exclude a possible part of the challenge or stakes.
Another impression: itself, lesser spirits, staying away from the uncomfortable warmth. Itself, as the oldest and largest and most capable of thought, stepping in first.
It proposes stakes. If the elemental wins, the young upstart practitioner continues with the claim, exactly as it is doing (even today, no possible stretch of memories and impressions can let the elemental manage pronouns), and surrenders the demesne to the elemental as soon as it earns it.
The ice mutters at the mouths of the sea. The elemental waits for Findekáno's answer. Despite the otherwise perfectly clear skies, it looks like it's snowing above the elemental's surface.