Sanrio Timenet (サンリオタイムネット) Catch Em All Guide: 152 Rexwalker (Past/Future)

In order to get 152 Rexwalker, you'll need to go to the Mysterious Shrine (Past World) or Mysterious Ruins (Future World); a dungeon you can access from New Continent (Past World) or Forgotten Continent (Future World) and you'll also need six specific monsters in the party.
Explore the dungeon until you find a magic circle, with a sign telling you that you need those six monsters. The monsters you need to bring with you are Patoran, Unchinrider, Angeln, Chikoppy, Erebian and Osuparu. These are the second stages of the starters between Past Version (Kako-Hen) and Mirai-Hen (Mirai-Hen). For ease in exploring the dungeon, it's recommended you raise them high (but not too high as for them to turn into their third stage evolutions) so you can escape from the monsters/use the Tekiyorasu (テキヨラーズ) "repel" to prevent encounters to your average level monster. It's also a good idea to bring a Dungeon Through (ダンジョンスルー) "escape rope" to instantly escape from the dungeon once you get Rex Walker. Both items can be purchased from shops, such as the Port Town (みなとまち)/Bay City (ベイシティ) shop.
You'll have to trade to get them all in one version, since the first stage monsters required to evolve once are exclusive to each version (Pikapochi, Unchinboya, Hyupo for Kako-Hen and Chikotto, Erebi, Eepy for Mirai-Hen). If you can't deposit/trade a monster, it might be because your bag would be full if you took all its Skill Packs/Power Marks; so toss some items if you can't deposit/trade it. Also, make sure the Pillar of Time is not full (PC isn't completely full of monsters); otherwise this will waste time - you won't be able to obtain Rexwalker until you clear it again and revisit the dungeon.
When you reach the magic circle with the required party, Rexwalker will automatically be added to the PC at Level 1. It is a Machine type monster. If you've played the spiritual sequel Space-Net, you might also know Rexwalker as Rex; the leader of the Kerocommand army for the crime syndicate called the Crackers.
Source: wikiwiki.jp/ti...

[@SRUFUS3D]

Thank you very much for uploading this information, Evie.

[@EvieMyMelody]

You're welcome. ^^