just about anything that has you spending mana to put a card on the stack and attempt to resolve it counts for expending
Im not gonna say casting multicolored spells is niche or hyper-specific, but giving Lilah, Undefeated Slickshot a specific condition like that is definitely a good slow-down on power creep, especially in an archetype like spellslinger, which uses tons of monocolored spells
Overload [cost] means "You may choose to pay [cost] rather than pay this spell's mana cost" and "If you chose to pay this spell's overload cost, change its text by replacing all instances of the word 'target' with the word 'each.'" If you don't pay the overload cost of a spell with overload, that spell will have a single target
Card Name Mana Cost Type Enchantment Aura Rarity Common rules Text Enchant creatureWhen this Aura enters, if enchanted creature has flying, this Aura deals 2 damage to that creature and this Aura gains "Enchanted creature loses flying." Number 0 Language English Legal Formats Commander, Legacy, Pauper, Vintage Not Legal Formats Alchemy, Brawl, Competitive Brawl, Historic, Modern, Pioneer, Standard, Timeless Rulings (10/4/2004) If the enchanted creature gains flying after Earthbind is put onto it, it will have flying
Although, Id prefer playing it as a creature in a Davros, Dalek Creator deck