Regeneration [Alpha Edition] Merfolk Wizard and what to do when

and what to do when either goes wrong

Set: Amonkhet Invocations Type: Enchantment Rarity: Mythic Cost: {7}{U}{U}{U} You may cast spells from your hand without paying their mana costs

unless you pay {B}{B}{B}

Only the splattered armor and ichor-stained sword hinted at the unfathomable evil the knight had just laid waste

Set: Commander Anthology Type: Artifact Rarity: Rare Cost: {3} You may activate abilities of creatures you control as though those creatures had haste

Regeneration [Alpha Edition] Merfolk Wizard and what to do whenSet: Alpha Edition Type: Enchantment Aura Rarity: Common Cost: {1}{G} Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.) {G}: Regenerate enchanted creature. (The next time that creature would be destroyed this turn, it isn't. Instead tap it, remove all damage from it, and remove it from combat.)