ever since slime blocks came out you have been able to store ender pearls (ever since 1.8) slime blocks were changed in 1.12 but the rotor still worked (but a little differnet) and in 1.13 the rotor no longer functioned correctly because of a slime block change. you can make any sort of clock to keep the slime blocks oscillating, even faster clocks than the one i used to have a better chance of keeping entities. Minecraft: Rotor (1.8.4) by pi314159265358978 https://www.youtube.com/watch?v=OqUFRiAP3GQ Tutorial] Simple Chunk Loading Setup | 1.13 - 1.13.2 by RagingDonut https://www.youtube.com/watch?v=0IaeLU5_qAk Quick And Easy: Wireless Redstone by Mumbo Jumbo https://www.youtube.com/watch?v=HrEm8z1e2r4 Minecraft teleport machine works in 1.8, 1.9, 1.10, 1.11, 1.12, 1.13, and most likely 1.14