How many bosses?

[Bullen]

How many bosses are there in the game?

[Skuvi]

lets see... Eater of worlds, brain of cthulhu, eye of cthulhu, queen bee, skeletron, WoF, the destroyer, twins, skeletron prime, plantera, golem and king slime. 12 bosses, 15 if you count pumpkin, mourning wood and wyrern. But this are more minibosses.

[Anarchisteve]

That really depends on how you define a boss. The easy mode bosses include the Queen Bee (perhaps more of a mini-boss but I'll include it anyway), the Eater of Worlds (in corrupt worlds) or the Brain of Cthulu (in crimson worlds), Skeletron, the Eye of Cthulu and, finally, the Wall of Flesh.

In hardmode you have the Destroyer, Skeletron Prime and the Twins (the mechanical bosses), Plantera and the Golem. There are also mini-bosses such as the Wyvern and the Paladin. Hope this helps (I think that's all of them but I may be forgetting someone).

EDIT: Obviously I did forget the King Slime (been a long time since I fought him) and the Pumpking.

[Emmote]

The King Slime is actually considered a mini-boss. It's so easy and it's the only boss that doesn't in some way, provide progression.

Every other boss either drops ore or gives you access to an NPC, new areas, etc..

King Slime also doesn't drop a trophy.

[Toamac]

引用自 FroZ Bullenx99：

How many bosses are there in the game?

7 pre-hard mode bosses,7 hardmode(1 for console and 1 for pc version),5 event bosses and Mobile Exclusive boss, so in total there 20 bosses for terraria as right now.red said that the lunar update will have one last boss unless he decide to add few bosses in addition to last one.

[Rellik66]

引用自 Emmote：

King Slime also doesn't drop a trophy.

Actually, king slime does drop a trophy[terraria.gamepedia.com]

[deltaTom]

if you are going to consider minibosses there is paladin ice queen everscream santa NK1 tht you have missed out

[Dr. McWeazel]

Technically, the Ice Queen, Everscream, Santa-NK1, Pumpking, and Mourning Wood are all proper bosses. While they don't spawn with the "[x] has awoken!" thing that most bosses do, they do boss level damage and have 5-digit HP.

[Torchfire]

You all are forgetting the Duke Fishron, which is technically an entirely optional boss, since it has to be spawned by players themselves, and does not advance the game in any way other than the endgame items it drops.

[Lotus]

引用自 Bullen：

How many bosses are there in the game?

Hey guys! There's also Ocram, the Moon Lord, (I love terrarium) the Golem, a mini boss is the big pirate ship

[Lotus]

Though there probably isn't anyone still playing Terraria accept me and a few others.....

[Anarchisteve]

This thread is nearly 5 years old, and those bosses were introduced later.
And there are quite a lot of people still playing it.