Notes & Combos
I reached to Legend 5 without XYZ block, so it's not really needed but it could help a lot when going first. I used a third Promoter and a sparrer for Turn 1 instead.
Some tips for new Boxers users:
If you can, try to keep 1 chief second on hand because it can save you from a lot of menaces like Lirylusc and it could get rid of XYZ materials and some "when summoned" effects. Also, chief second negates the attack AND removes a monster, so if you use its effect to negate the Monster 1 attack, you can banish MOnster 2 so it can't attack.
C79 is your best tool against synchro, XYZ and Links, but its negation wouldn'y work against special summons that start a chain (i've learned this the hard way lol). In turn 1 rank up 105 to have it against liry, salad or revolution des fleurs.
Try to send Uppercut as cost for ability or as cost for Dempsey skill asap, because you want it in graveyard for Flamvell Counter.
And last but not least, try to detach glassjaw as chain 1. If not, the effect lose its activation window.