| Auction house — escrowed bids, gold that cannot be printed | 124 | a state machine, a memory invariant, try / catch |
| Battle pass — every tier reward claimed exactly once | 92 | a state machine, a memory invariant, try / catch |
| Battle turns — nobody acts twice, and the dead stay dead | 89 | a state machine, a memory invariant |
| Crafting forge — ingredients consumed exactly once | 98 | a state machine, a memory invariant, try / catch |
| Daily chest — one claim per day, clock tricks be damned | 57 | a state machine, a memory invariant, try / catch |
| Gem store — a purchase receipt credits exactly once | 101 | a state machine, a memory invariant, try / catch |
| Guild bank — the heist needs a key an expelled member cannot hold | 102 | a state machine, a memory invariant, try / catch |
| Harvest node — one vein, one yield per respawn cycle | 79 | a state machine, a memory invariant, try / catch |
| Loot roll — one roll per raider, one award per drop | 84 | a state machine, a memory invariant, try / catch |
| Loot trade — an item exists in exactly one inventory, ever | 101 | a state machine, a memory invariant, try / catch |
| Pity banner — the 90-pull guarantee that cannot be skipped | 73 | a memory invariant |
| Seasonal ladder — decay you cannot dodge, ratings that cannot underflow | 98 | a state machine, a memory invariant, try / catch |
| Stamina — the energy bar that cannot be overfilled or driven negative | 68 | a memory invariant, try / catch |
| Tournament bracket — eliminated means eliminated | 73 | a state machine, match, try / catch |
| Veterancy ranks — promotion is earned and can never be rolled back | 92 | a state machine, a memory invariant, try / catch |
| Wager duel — staked gold that exactly one fighter can win | 122 | a state machine, a memory invariant, match, try / catch |