The battle system of Paper Mario: Sticker Star is entirely based on the use of stickers: Mario doesn’t have any stat except for HP, making Boss Battles somewhat harder, requiring a precise strategy to complete and the use of specific stickers.
The first boss has a total of 90 HP and it’s not hard at all: forst you’ll battle some goombas that, after a couple of turns, will unite into the bigger Megasparkle Goomba. Just fight the normal goombas and make sure to avoid all their attacks: after they unite use a Scissor Thing Sticker to deal a lot of damage. If you make the Goomba soggy or crumpled you’l deal double damage, making the battle even easier.
Now thing’s get serious: this boss has 300 HP total and it requires the Bat Thing Sticker to make things easier. At the beginning the boss’ body will be buried under the sand: wait for all of it to come out before using the Bat Sticker! During the battle you’ll have to face two green pokeys: the fastest way to deal with them is the Fire Flower Sticker. Be careful that the boss will heal ten HP each turn after getting low on HP: try to make him soggy to increase deal damage.
The Gooper Blooper boss battle isn’t too hard if you know what you’re doing. The boss has 300 Hp total and the Sponge Thing Sticker will make the battle go smoothly. Fight the boss normally and wait for it to place its head halfway into the water, turning purple: that’s the cue to use the Sponge Thing Sticker which will absorb the poison shots launched by the boss and shoot them back at him! Once poisoned, the boss will take 30 HP damage every turn, together with lowering its attack and defense for 5 turns.
This boss, more than the others before it, requires some preparation to beat: bring as much fire based stickers as you can. The boss has 400 total HP and will fight you as a Bowser Snow Statue until he’s at 100 HP. The Bowser Statues get progressively weaker as the battle goes on but they can freeze Mario; the true form of Mizzter Blizzard attacks Mario by throwing snowballs and he’s no threat at all. Just be careful and avoid freezing at any cost.
The World 5 Boss has a total of 300 HP and attacks Mario in many ways: slamming on him, spitting a ball of goo causing the soggy status ailment and using its spinning leaves to cause damage. This last attack makes the boss dizzy after using it, showing its weak spot, making attacks more damaging. After being hit on its weak point, the boss will spit out Kersti and a Dry Bones. After reaching critical condition he’ll use another bite attack on Mario, causing up to 21 points of damage. Other than damaging the weak point, there’s no other strategy: try to avoid all attacks, especially the bites, and use your best stickers.
Bowser is the final boss of the game and the battle will be divided into five phases. Bowser’s attacks will be the same throught all phases: a spin, a fire attack and an air pound which can all be blocked except for the spin since you can only reduce damage. To be able to use Jump attacks against Bowser you can only use the Iron Jump family of stickers since Bowser’s shell has spikes. Using the Megaflash stickers is the way to go to get the highest damage possible. During the first phase use the tape to seal the openings and prevent new enemies from entering the battle; in phase 2 you’ll have to defeat a whomp enemy with 50 HP and Bowser gets fully healed; in phase 3 Bowser’s Max HP will rise to 350 and will shoot fireballs to the side: use an ice based attack to freeze them; in phase 4 you’ll face a chain chomp and Bowser gets healed again: to end this phase quickly use a Tail type sticker and press A when the chain chomp gets close to hurl him back at Bowser. In the final phase Bowser has 500 total HP and he’ll have three targets: keep fighting using mid-level stickers until Kersti turns herself into an album, giving you five sticker slots per turn and increased power. Unleash all your best stickers and Bowser will become history, at least for this game!