Fees, bank & jackpot

Every lamport in BurnBola moves along fixed, auditable rails. There are exactly two fees in the whole game — both 10%, both visible on-chain.

Fee #1 — the buy-in fee (10% of the ticket)

When you buy a ticket for 0.1 SOL:

Where	Amount
Game bank (the pot)	0.09 SOL
Buy-in fee	0.01 SOL

The entire buy-in fee funds the referral system: 6% of the ticket to your direct inviter (L1), 3% to their inviter (L2), 1% to the next level up (L3). Any level that doesn't exist — you joined without an invite, or the chain is short — goes to the lottery treasury instead. (Referrals.)

Fee #2 — the round commission (10% of the bank, per round)

At the start of every round from round 2 on, the contract takes 10% of the current bank and splits it:

Share	Goes to
75%	the jackpot — sealed until the end of the game
20%	the lottery (in round 2, half of this one-time feeds the autonomy reward vault)
5%	the cross-game leaderboard pool (Leaderboard)

Round 1 takes no commission — the first collection happens when round 2 opens.

The bank

The bank is the game's main pot: 0.09 SOL × tickets sold. From the moment the game starts it only decreases — by round commissions and by exit payouts. Whatever remains at the end belongs to the winner. The bank lives in a program-owned vault account; no human holds its keys.

The jackpot

The jackpot is the winner's bonus, accumulated from round commissions (75% of each). Its key property: exits can't touch it. Even if a horde of players exits and drains most of the bank, the jackpot stays sealed for whoever survives to the end. The longer the game runs, the more rounds have fed it.

• One ticket survives → it takes remaining bank + the whole jackpot.
• Zero tickets survive (everyone exited, the rest burned) → the jackpot goes to the lottery treasury. It does not roll into the next game — each game's economy is closed.

What the lottery itself earns

The house takes no rake from the bank beyond the flows above: unclaimed referral shares from the buy-in fee, the 20% slice of round commissions (~2% of the bank per round), and the jackpot in the rare no-winner case. All of it accrues in a treasury vault whose withdrawal destination is hard-wired in the contract — even the operator key can only send revenue to the one published treasury address.

Worked example — a 100-ticket game

• Sale: 100 × 0.1 SOL = 10 SOL in. Bank = 9.0 SOL, referral system = 1.0 SOL.
• Round 2 opens (50 alive): commission 0.9 → jackpot 0.675, lottery 0.18, leaderboard 0.045. Exit price = 8.1 / 50 = 0.162 SOL.
• Suppose 10 tickets exit (−1.62 SOL), then round 3 opens (20 alive after the burn of 40): commission ~0.65 → jackpot ~0.49 … and so on.
• By the final round the last ticket standing collects whatever bank survived the exits plus a jackpot that grew every single round.

The exact trajectory depends on how many players exit when — that's the game. The rails the money rides on never change.