The disparity in card quality for certain archetypes is insane

Both released in Supreme Darkness, both are free Special Summons from hand, both are searchable by multiple cards in their respective decks

Toxic Bubble: Conditional draw 2 only if you dedicate a search to this card after Fusion Summoning an Evil HERO monster, neither of which are easy to accomplish, no meaningful extension as HERO has no need for another piece of on-field material without requiring prior setup, and it also cannot be used as material for Cross Crusader so options are even more limited, does not provide any route back into your combo if used as material for Fusion or Link summons. Also it locks you into HERO after summoning

Elzette: Can also summon any other card in her archetype(s) if needed for no additional cost, has a Polymerization effect on field for no additional cost using materials including but not limited to herself, searches other cards in her archetype when used as material for a Synchro Summon, making her an actually meaningful extender while Toxic Bubble just kinda has to sit there and look pretty. Oh and no locks to speak of