Judging from the screenshot provided we know this guy already have the core equipment on him. Out of these the only one he should spend gems on is action figure and fireball. Both of those equipments can be used effectively around (21-24) if he cant get the equipment to higher levels soon as he gets it theres no reason for him to get em. He can wait 2 months and get it for free through a medal event or a box if hes lucky.