- Playable version of the Big Dog boss. A character that's tricky to use mainly because it's so slow and big, and can easily hurt itself with it's own explosives. Added as an April Fools joke.
- Big Dog starts with 300HP, 255 bullet ammo and 55 explosive ammo.
- Pressing LMB triggers Big Dog's Spin Attack that costs 15 bullet type ammo. Big Dog spins very quickly, and lines of slow moving projectiles spiral out of its body. Each projectile does 3 damage.
- Big Dog can't use or pick up any weapons. It is also larger and slower than other characters.
- Pressing RMB fires three slowly moving missiles that follow your cursor. Using the special costs 3 explosive type ammo. Missiles will explode on collision with walls, props and enemies. This special doesn't have reload time but it's not automatic.
- Each missile deals 5-10 explosive damage and no impact damage. They bounce off Big Dog but he still takes damage from explosions. The missiles will always drop ammo and health pickups. Each missile has 22HP and will explode upon taking too much damage from enemy projectiles or other missiles exploding.
- Throne Butt makes Big Dog's projectiles and missiles move faster.
Ultra SpinSpin Attack fires double the amount of projectiles.
Ultra MissilesMissiles constantly fire projectiles. Each projectile deals 3 damage.
- The main drawback of Big Dog is its size and movement speed. Its health and the destruction he can do from the start of the game make up for that. Tight corridors are not much of a problem since you can just blow them up. Best way to use the missiles is to fire a few and at the same time walk in the opposite direction, that way you won't get caught up in the blast. Running low on HP can be easily countered by firing a bunch of missiles into a wall, and collecting ammo and health drops those missiles leave behind. Since missiles explode if they take too much damage, the best way to kill enemies is to use the Spin Attack, using missiles only when there are no enemy projectiles near Big Dog. Having mutations like Gamma Guts and Sharp Teeth gives you a way to deal with contact damage enemies. Starting with a Crown of Hatred gives you easy access to Big Dog's Ultra Mutations.
- Useful mutations:
- Boiling Veins - Veins decreases the amount of damage taken from explosions, so while immunity at 4 HP isn't useful, Big Dog will be hurt less by his missiles in general.
- Sharp Teeth - Damage is unavoidable as Big Dog, so Sharp Teeth is a must to have a constant output of damage. Damage taken from his own missiles can also be utilized with this mutation.
- Gamma Guts - Enemies charging at Big Dog are hard to deal with and this mutation will do damage to them.
- Extra Feet - Makes it a bit easier to avoid projectiles than with Big Dog's default movement speed.
- Throne Butt - A direct upgrade to Big Dog's abilities.
- Back Muscle - Also a direct upgrade to Big Dog's abilities, increases the amount of missiles and projectiles you can fire, before running out of ammo.
- Second Stomach - Big Dog's missiles drop a lot of health pickups, with this mutation Big Dog will heal up much faster from them.
- Plutonium Hunger - Can be paired with Stomach, allowing Big Dog to heal much faster than he is being hit, as his missiles will constantly drop ammo and HP.
- Recycle Gland - The only weapon specific mutation that works with Big Dog, but its easy to replenish bullet ammo with pickups dropped by missiles.
- Because of Big Dog's 300 default health and its inability to use weapons, some mutations aren't very useful, those include:
- Rhino Skin - Raises Big Dog's health to 304.
- Strong Spirit - Big Dog on 1 health is almost certain to die and almost impossible to get to full health again.
- Laser Brain, Bolt Marrow, Eagle Eyes, Long Arms, Shotgun Shoulders - Don't work with Big Dog.
- Big Dog is unlocked by defeating Big Dog.
- Is only available on April 1st, and only through steam's current open beta of the game.
- Big Dog was originally added as a playable character on 1st of April 2015, as an April Fools joke, and removed a week after in update #67.
- After beating the Nuclear Throne boss with Big Dog, Large Weapon Chests will randomly turn into Weapon Chest Mimics for every character. (this was an April Fools joke made by Gieron, Weapon Chest Mimics existed only as a wiki page)
- Big Dog had two Loading Screen Tips: