The eighteenth level in Challenge mode in Pikmin 2. If this cave doesn't want to give you the pink flower you deserve, then here's some help.
Pikmin
25 Red 25 Blue
Sprays
Spicy: 1 Bitter: 1
Sublevels
2
Sublevel 1
Start off by collecting the treasure lying around, if you want, then start looking for a Watery Blowhog and a pipe. Kill the Blowhog and go down the pipe, where you should see some fire geysers. Continue walking and you'll see a Fiery Bulblax. Use an Ultra-bitter spray and your Reds. Snatch the key, watching the Pikmin carry it because Dweevils might appear: make sure they don't take the it. Next, grab some more treasures if you like, and then go down the hole to...
Sublevel 2
The high-strung, hungry Orange Bulborb has the key we need. Use your Ultra-spicy spray. Sneaking up from behind is best, but most of the time he's in a small room, making that impossible. If you don't like his placement, reset the cave. Grab some treasure, since there should be lots of time (there is also LOTS of treasure). Open the geyser and exit for the pink flower you wanted!