The randomness proof is cryptographically bound to the input caller_seed and to MagicBlock’s VRF signer identity. Your callback enforces this with: 
#[account(address = ephemeral_vrf_sdk::consts::VRF_PROGRAM_IDENTITY)]
pub vrf_program_identity: Signer<'info>,
Only the official MagicBlock oracle can trigger the callback, preventing spoofed or manipulated results. Invalid proofs automatically fail, and other programs cannot front‑run the request. EphemeralVrf checks for conditions like InvalidProof and Unauthorized so incorrect signatures or unauthorized callers are rejected before your game logic runs. The implementation has not been audited yet, so always monitor callbacks in staging before going live. Avoid letting users provide the entire caller_seed directly—combine it with game state or timestamps to prevent seed grinding. Because everything executes inside the deterministic rollup, the random value cannot be reused or delayed. This enforcement happens within the same ephemeral rollup that executes your game logic.