When you're journeying down the hole in level two, you can attack the crows multiple times. After several hits, you will recieve a life. This is the case with every crow.
after completing most of the level 3 race thing, you will encounter the harder part of the track, where the blocks come real fast. After 4 blocks have past on the bottom alone, stay bottom, and u will enter the warp thing, skipping the ice level, this is good if u dont like the ice level! there is also a warp on level one (the white shimmering circles on the platform) but it only stays for a little bit. i do not use this one tho, cos it skips level 2, where u can get many lives by repeatedly kicking the birds against the wall! enjoy
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Level Select: Up, Down, Up, Up, Down, C, A, B