Snake Boss

• The boss of Mirna. The spawner tries to drop a boss in every 600 seconds of run time, and it is blocked while a boss is already out or while you are extracting.

• Push resistance 1: a hit staggers it the normal amount.
• Loot chance does not apply to a boss. A boss drops its own reward when the fight ends, not on this roll.
• Experience given also rises with the run's monster strength, by the same multiplier as its health.
• Damage threshold 5: inside the Magus Circle mansion only, every 5 damage it takes shakes an extra pickup loose. It does nothing in the four regions.

• Boss. Runs a scripted fight of its own instead of joining the wave. Stun, freeze, chill, polymorph and knockback do not stick to it, and touching it costs the same as touching an elite.

Contact

Touching it costs you one point of health, plus whatever the run's Heavy Hitters bonus adds, because it is a boss. A monster that is frozen, stunned or polymorphed cannot hurt you by contact.

No immunities and no special movement behaviour.

Once its health drops under half it moves into its second phase and its attacks come half again as fast for the rest of the fight.

In Mirna: the run's monster strength starts at 1 and moves +0.5 every 300 s; +0.25 every 150 s; +0.1 every 120 s; +0.1 every 60 s; +0.1 on reaching stage 3 of the roster; +0.25 on reaching stage 4 of the roster; x5 on reaching stage 5 of the roster.

In Yawm, Elysia, Yomori: the run's monster strength starts at 1 and moves +0.5 every 300 s; +0.25 every 150 s; +0.1 every 120 s; +0.1 every 60 s; x5 on reaching stage 4 of the roster.

Where two of these steps land on the same second, only one of them fires: the region's own page shows which.

In Mirna, the first boss fight also adds 20, as long as the first death scene has not played and you have died fewer than 2 times.

Once the multiplier is above 1, this enemy spawns with its base health multiplied by it: 2500 health at 1, and a multiplier of 2 makes it 5000, 5 makes it 12500. The experience it gives is multiplied the same way.

Other things change this monster on top of that. Hard mode gives it 2 times its health and 1.25 times its speed. The energized run modifier gives every monster 1.25 times its speed. While you are extracting, every monster moves 1.15 times as fast. Each time a region's roster runs past its last stage, every monster except bosses gets +0.25 to its speed multiplier, up to 2 times its speed.