This enemy is the Alien variant of St. Pigge the 2nd. She has high health but relatively low damage and range. However, she has 100% chance for a Lv. 3 Wave Attack, so she will punish the player for spamming meatshields.
To beat her in New York, use only strong, high-health troops, such as Whale Cat and Mythical Titan Cat. It is not recommended to stack rangers with low-mediocre health against her such as Macho Legs Cat as they will easily get knockback and die to her long shockwaves.
Anything that freezes Aliens and is decently bulky such as Surfer Cat, who can rush in without getting knocked back, can immobilize Elizabeth the LVIth, allowing other units to attack her without trouble (e.g. Valkyrie Cat).
If you are fighting Cli-One or Corrupted Valkyrie in Into the Future's Moon stages and Elizabeth spawns, that is a sign that you have taken too long to beat the stage and that everything is about to go horribly wrong. Either retry the stage, or come back later when you're stronger.
In a late-game scenario she is pretty easy to deal with because of the Wave Shield ability that is on a variety of units and also because she has low damage for a wave attacker. It will be especially hard for her to deal with a stream of Octopus Cats unless heavily magnified. If you were lucky enough to receive one of these ubers, then they will be able to deal with her easily. Using other units with the Wave Immunity or the Wave Shieldabilities are also helpful when fighting her.
56th queen of the Pigpen Kingdom. She turned blue after 7 mushrooms got stuck on her throat, causing her to choke. Moves around without permission using a crown she found around. Can release shockwaves.