From the Super Mario Wiki
Tap-Tap the Golden is a giant golden invincible Tap-Tap found in Door Three of Baby Bowser's castle in the game Super Mario World 2: Yoshi's Island. The screen slowly moves through a lava-filled cave as Tap-Tap the Golden chases after Yoshi. It can be hit into the bottomless pits, but it will only come back. Knocking it off of the screen is the best option, and several Fangs are around to supply Yoshi with eggs for repetition of this strategy. It is worth noting that Tap-Tap the Golden will actually jump over Yoshi if he gets too close, instead of attempting actual harm. The mini-boss is invincible in normal gameplay, but can be defeated through hacking.
Different golden Tap-Taps, called Super Big Tap-Taps, appear in Yoshi's Island DS. They are much larger than Tap-Tap the Golden and attack Yoshi in a manner similar to Chomp Sharks.
Tap-Tap the Golden may be Tap-Tap the Red Nose resurrected, as the Nintendo Power Guide introduces it with "Tap-Tap the Golden is back", though this is likely an error.
Tap-Tap the Golden reappears in Yoshi's New Island in Baby Bowser's Castle Break-In.
- ^ Super Mario World 2: Yoshi's Island Nintendo Player's Guide. Page 128.