Gyromancer

The map has a central circular section with separate sections North, South, East and West. The North section contains a Boss and is blocked off by flaming barriers. The South, East, and West sections contain switches that remove the barriers and can only be teleported to.

The teleporters require beasts of a certain affinity color for you to use them, so you need to outfit your Beast Roster accordingly to use each teleporter in one playthrough:
South = Yellow or Purple affinity
East = Blue or Silver affinity
West = Red or Orange affinity

My roster at time of creating this guide:
Level 62 Sol Volk, 13520 HP (yellow)
Level 62 Aspidochelon, 19400 HP (blue)
Level 62 Grendel, 15480 HP (orange)
-- I leveled up to 65 by the time I arrived at the Boss

Each teleport section contains switches and several enemies, including a mini-Boss. After defeating each mini-Boss you can collect their Gyro Code to add them to your roster at the Summoner's Den.

East enemies
Level 52 Juggernaut, 14740 HP (silver)(switch guard)
Level 52 Garutman, 9760 HP (silver)(switch guard)
Level 52 Behemoth, 16400 HP (blue)
Level 52 Leviathan, 14740 HP (blue)
Level 54 Nahar, 18720 HP (silver)(mini boss)

South enemies
Level 52 Cerberus, 11420 HP (yellow)(switch guard)
Level 52 Hecatoncheir, 13080 HP (yellow)(switch guard)
Level 52 Manticore, 8100 HP (purple)
Level 52 Beelzebub, 13080 HP (purple)
Level 54 Resheph, 10120 HP (yellow)(mini boss)

West enemies
Level 52 Wendigo, 9760 HP (red)(switch guard)
Level 52 Brass Wyrm, 9760 HP (red)(switch guard)
Level 52 Dullahan, 18060 HP (orange)
Level 52 Fafnir, 13080 HP (orange)
Level 54 Motu, 15280 HP (red)(mini boss)

Central enemies
Level 50 Paleofungus, 11000 HP
(there are 4 of these, but you only need to defeat one of the upper two to navigate the center)
Level 53 Alraune, 15010 HP (guards North section and a switch)

North boss
(directly under the boss is a spot that fully heals your beasts... use it if you need it)
Level 55 Scion, 19050 HP (blue)(final boss)

I barely took any damage while progressing through the map, so after the full heal, I thought this boss is toast. The Scion starts out with 3 ability gems on the board and it initially seems overwhelming. But once you get things going, all falls into place for a good showdown and eventual victory. Use your items if you have to. Try not to make too many idle twists. Eliminate as many of the enemy gems as possible but don't be afraid to take damage if it is minimal. I beat the Scion with one beast on the first try at level 65. I'm sure lower levels could beat it also.