@Lord_Wasabi, then the filter should work with the sample document in the image you had attached in the earlier comment:
{ $expr: { $lt: [ "$stats.currentHP", "$stats.maxHP" ] } }
@Lord_Wasabi, then the filter should work with the sample document in the image you had attached in the earlier comment:
{ $expr: { $lt: [ "$stats.currentHP", "$stats.maxHP" ] } }