If you target multiple monsters with "Telekinetic Power Well" and an effect is chained so that one or more monsters are not in the Graveyard at resolution, then "Telekinetic Power Well" Special Summons as many monsters as possible. Then, you take damage equal to 300x the Levels of the monsters that were Special Summoned.[3]
↑ abKonami FAQ: Does the effect of "Telekinetic Power Well" target the Level 2 or lower Psychic-Type monsters in your Graveyard?
↑Konami FAQ: When "Telekinetic Power Well" Special Summons a monster and you take damage, after it resolves is it treated as both occurring simultaneously?