Well went to Toys r Us for my Wave 4 hunting today 3/23. There was nothing left except for a few core characters. There was ZERO Thunderbolt, Short Cut, Echo, Spotlight, Blackout, Knightmare, and Knightlight. They still had some Easter Traps as well as some Eggsselent Weeruptor. Power Punch Jet Vac won the award for the most unloved wave 4 character as there was well over 20 of him (he doesn't scream easter to me anyways). Mind you I did go the day of launch and they had amazing stock of everything. I am convinced the scalpers have found there way to my area. Because usually it doesn't disappear so quickly.
I did manage to pick up batspin and rocky roll. Also keep in mind there is a buy one get on 40% sale this week on Trap Team Skylanders and Traps if you are lucky enough to still have wave 4 stock at your store. Happy Hunting