This achievement is story-related and can't be missed.
It will unlock after beating Stage 2 on normal or casual mode on your first playthrough.
This boss uses the following pattern when attacking:
- Shoots two blasts of ice balls, one horizontally and other moving above the horizontal one - To avoid, simply stay crouched, preferably near him with Miriam so you can hit him with standard strike
- Even before the ice balls cease, the 3 spikes on the roof will fall - To avoid, simply don't stay right below any of them;
- Around 2 seconds after the spikes fall, he will charge you horizontally - To avoid, use a well timed jump, preferably with Miriam;
- After charging, 3 pairs of stones will fall from the roof and the boss himself will also fall over you - This is very hard to avoid! Stay in the middle of the stones and try to jump away immediately after the third pair of stones;
- Lastly, he will put a circle of ice balls moving around him - To avoid, hit the ice balls to gain space and move to wherever you can.
To beat him, use a mix of standard strikes
and special strikes
whenever you can while avoiding his attacks.
Please refer to this video by YouTube user DenSetsu for the complete fight: