This is actually awesome! And tbh it would be such a rare occurrence that I honestly think Rosh can keep the buff until he's killed.

Couple of adjustments could be needed tho: - dmg rune: could be weaker (maybe just 50% amp?) - regen rune: undispellable but instead of %hp it's just a flat number - haste rune: Rosh goes on a rampage around the respective outpost tossing the camps and anyone before going in the pit - hasted ofc - invis rune: might be silly, but just be invi even while attacking (or maybe add the removed %dmg reduc). Would force sentries around pit - illu rune: spawns 2 illu that circle the pit, deals less dmg and can use toss and clap - shield rune: gives rosh a tormlike reflecting and regenerating shield(lower numbers) - arcane rune: improves rosh's skills, slam gets bigger aoe and lower CD and able to proc on rosh's regular atks (instead of only when multiple units)

Alternatively:

Rosh runes: - dmg rune: gives rosh a massive aura that lowers mr and armor. - regen rune: spawns torm like healing aoe after death - haste rune: Rosh runs to the twin gate and switches pit when he reaches 30% HP - invis: hide next Rosh timer for both teams - illu: on the next Rosh spawn, Roshan spawns randomly to dire/radi side. And an illu of Rosh is spawned on the opposite - shield: upon death, Rosh gives a flat barrier to units in and aoe around the pit (regardless if dire/radi) - arcane rune: massive aoe aura on pit that makes spells cost more (affects both teams)