Helm of Chatzuk [Summer Magic / Edgar] XY98 and what to do when

and what to do when either goes wrong

Set: Gym Challenge Unlimited Type: Colorless Rarity: Holo Rare

Set: Vanguard Series Type: Vanguard Rarity: Rare Whenever a creature deals damage to you

Set: Promo Finish: Cold Foil Type: Action Subtype: Item Rarity: Promo Class: Generic Cost: 0 Instant - Destroy Energy Potion: Gain [2 Resource]

Helm of Chatzuk [Summer Magic / Edgar] XY98 and what to do whenSet: Summer Magic Edgar Type: Artifact Rarity: Rare Cost: {1} {1}, {T}: Target creature gains banding until end of turn. (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding a player controls are blocking or being blocked by a creature, that player divides that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)