Platform: macOS
Format: 100-Card Brawl

Description of Bug:
I cast "Arachnogenesis" during the Declare Blockers step. The spell resolved and successfully created Spider tokens, but it FAILED to prevent combat damage from the opponent's non-Spider creatures.

The opponent was attacking with "Ghalta, Primal Hunger" (modified by "The Earth Crystal" and "Blanchwood Armor") and "Toph, Earthbending Master".

Rules Confirmation:
- There were NO "Questing Beast" effects on the battlefield.
- There were NO "Damage can't be prevented" spells (like Stomp/Bonecrusher Giant) in the Graveyard, Exile, or Adventure Zone.
- The attackers were not Spiders.

Suspected Cause:
There appears to be a layering or rules engine failure regarding damage prevention when interacting with the new "Avatar" set mechanics (specifically Toph or The Earth Crystal), causing valid damage prevention effects to be ignored.