Cave Story's Secret Santa

In zone 2, top left house : Snake House, you can easily farm by womping two patrols per interval (womp one, womp the other, go back to the first one, repeat 50 times)

You don't have to wait patrols to be "ready", you can womp them when they have a "?" over their head.

This guide contains all secret area so you can find easily those cookies : Steam guide by zipeater

Once you eat all 19 cookies, you have to go into the final house, finish the cutscene and the achievement is yours

You don't need to visit ALL houses to trigger these achievements.

I recommend to do another playthrough (new game) to try these.

Avoid all extra houses, be cautious (especially on last house of zone 2, LShaped House), don't eat cookies (obviously) and these will be easy.