Solvency & Safety

Platform guarantees and safety mechanisms.

Solvency Enforcement

Every gacha creation undergoes a solvency check:

REQUIRED: price × cards × 0.99 ≥ sum(card_fmv) × buyback_rate

If FALSE: Gacha creation REJECTED

Example: Solvent Gacha

Cards Pull Price Buyback Card FMV Total Check
20 $25 90% $556 (25×20×0.99) vs (556×0.90) = 495 vs 500 ✗ FAIL

Example: Insolvent Gacha

Cards Pull Price Buyback Card FMV Total Check
20 $20 90% $500 (20×20×0.99) vs (500×0.90) = 396 vs 450 ✗ FAIL

This gacha would be rejected. You can't cover buybacks.

What the Platform Guarantees

Guarantee How It's Enforced
NFTs exist in vault On-chain verification at creation
Solvency Formula enforced at creation
Randomness is fair TEE hardware-backed (Intel TDX)
Transfers occur Optimistic locking + on-chain verification
Buyback processing Admin-batched with on-chain verification

What Is NOT Guaranteed

Gap Note
Card value accuracy Creator self-reports at creation
Market value NFT prices can fluctuate
Buyback timing Manual batching (24-48 hour delay)
SOL/USD conversion Direct comparison, no oracle

TEE Randomness Verification

Every pull uses hardware-verifiable randomness:

  1. Seed Generation: Intel TDX enclave generates random seed
  2. Attestation: Cryptographic proof from hardware
  3. Verification: Platform verifies attestation before using seed
  4. Selection: card_index = seed % pool_size

You cannot: - Predict the next card - Manipulate the outcome - Front-run the system

NFT Vault Security

Aspect Security Measure
Private key Never exposed — lives in TEE enclave
Transfers Only via TEE-signed transactions
Authorization TEE_VAULT_API_KEY bearer token
Audit trail All transfers logged with tx signatures

Buyer Protections

  1. Escrow — Payment held until NFT transfer confirmed
  2. On-chain verification — Every transfer verified via RPC
  3. Retry mechanism — Failed transfers can be retried
  4. Buyback guarantee — If creator has funds (solvency check passed)

Creator Protections

  1. Platform fee only 1% — Low cost of operation
  2. No upfront gacha fee — Free to create
  3. Variance warnings — System alerts if max/min ratio > 10x
  4. Card pool locked — Once created, pool can't be modified

Known Limitations

Limitation Impact Mitigation
Self-reported values Creator could overstate Due diligence required
No price oracle SOL/USD may drift Verify prices independently
Manual buyback payouts 24-48hr delay Platform monitors queue
Single vault wallet NFTs commingled TEE enforces authorized transfers only

Best Practices

For Buyers

  1. Verify card values on secondary markets before pulling
  2. Check the gacha's solvency (ask the creator)
  3. Consider buyback rate — higher is safer

For Creators

  1. Source cards at 40-50% below FMV
  2. Price pulls at 75-80% of FMV
  3. Keep buyback rate reasonable (85-90%)
  4. Increase card count to reduce variance

Emergency Procedures

Scenario Action
NFT transfer fails Retry via /pull/:openingId/retry-transfer
Vault health issues Platform pauses new purchases
Creator dispute Contact support with tx hash

Reporting Issues