If you want to use reworked New Year Tobirama you should consider spending your moon coins into maxing battle armor level since Battle Armor Rebate max level was changed and gives free 80 frags of New Year Tobirama (and some power value that comes from battle armor ofc). It will take some time but you can think of it as a "free" bonus that will happen over the time. [unless Oasis changes reworked Tobirama in that rebate but that would be really aids move]

Careful reminder that Im not sure what side of that event works like that but one of those only gives you rewards when you level up battle armor DURING the event period. If you level it up with out the rebate you don't get the reward.