What we know
Panel reporting says character presentation can switch between SD and HD while the world receives lighting, water, fog, shadow and particle upgrades under a Classic-focused art direction.
What beta needs to answer
Per-character vs global toggle
NPC model behavior
Performance cost
Texture options
Water / shadow settings
Minimum hardware impact
Verification status: this is an announcement-day system page. Exact values, unlock requirements and restrictions will be added only after Blizzard documentation or direct beta verification.
Current source: BlizzCon panel report ↗