Paper Mario: Color Splash - How to find the Bone to beat Iggy in the Golden Coliseum
The fight against Iggy at the Golden Coliseum is interesting if nothing else. Like most of the bosses in Paper Mario: Color Splash you need a specific Thing in your deck of cards to best him, and if the admittance Shy Guy is any indication that Thing is a Bone. He does say it enough, after all.
Wandering around the Coliseum, you meet some Shy Guys trying to find a weapon they stole from Marmalade Valley. It's obvious this weapon is the Thing you need, but if you travel to Marmalade Valley to find another Bone to take to the fight a Toad will tell you it's been stolen. You can't buy a new one from the Wringer in Port Prisma either, and the know-it-all Toad tells you the item is in the Golden Coliseum.
From here you head back to the Coliseum and speak to the admittance Shy Guy inside the Golden Coliseum he asks if you're bad to the bone. Normally you'd say yes -- that seems like the natural thing to do -- but instead you need to respond with "I.. I don't know..." and the Shy Guy sends you on your way.
Now you can finally explore the area to find the Bone.
From here you need to go back outside the Coliseum and go left toward the spectator area, which was closed before you declined to fight but is now open.
You've got to make your way from the third level of the stands to the first, which is a downward trip filled with blank spots to paint, disgruntled fighters to combat, Fuzzies to dodge, and cards to pick up.
The entire trip is hard to describe but it's easy to figure out which way you're supposed to go from here -- though you will have to use an Unfurl Block at one point, and you need to go behind the stairs on the first level of the stands (check the signs on each floor).
On the ledge outside the first level of the stands you'll notice a spot where there are two blocks that fall when you step on them with two Fuzzies patrolling the area. Let the block to the left without spikes under it drop you, then walk left.
Finding the Bone from this point on is easy. When you reach the spying Goomba, walk right for a save point and the Bone.
You can also find a Bottle Opener in the Coliseum's spectator area, which also requires you to adventure around the first floor of the area but without purposefully falling as you did to get the Bone.
You don't need the Bottle Opener to beat Iggy, but it's good to go ahead and grab it now.
As for Iggy himself, be sure to use the bone once he and his two minions are out on their chariots. Iggy will call out his minions once he is at half health, and on the turn right after he won't be present. Do not use the bone until all three enemies are on the field.