Counter Tips

Chrom recovers by using a sword up and with him to aim the ledge. Grab your Luma, drop down and spike down. Rosalina alone won't work most of the time since it's not powerful enough to send him home.

Always keep ur Luma separated but to far. Incase you get knock out, Luma can give a little punch so he won't Edge guard you. Also use side B respectfully and use aerial forward for damage staking.