Survival Modifiers to Trial Spawners

Short version: the 8x8 ring of blocks at the base of a Trial Spawner let you change the composition of the fight without mods, Creative, resource packs, or NBT. The game associates each Hostile Mob with a specific Block, and the ratios of what's been placed can allow for unique fights (up to 8 different mobs or varieties in different ratios). Specifically this is meant to enhance the Replayable, Survival element of the structure, and minimize map size bloat where it's a problem.

The reasoning: I love that we can tell what a Trial Spawner may generate due to the blocks beneath it, but what if that became part of the GUI/interface for the block? This also (importantly) reduces the need for SMP Servers to keep expanding their map size or worry about lag - few/one Spawner can serve most needs!

Example given: x4 Packed Ice denotes full composition of Strays. Other concepts (what blocks are priced similarly, or make more sense?) could include...

Magma for Magma Cubes, Slime Blocks for Slimes, Honeycomb for Angry Bees, Iron Blocks for Angry Golems, Snow Blocks for Angry Goats, Gold Blocks for Hostile Zombified Piglins, Emerald Blocks for Pillager Patrols, etc... Some blocks could merely reference a mechanic, others could be on-the-nose like Bone Block for Skeletons. (Any zombie variant has a chance to be a baby, because suffering)

(Thought: probably nothing should come from the Trial Spawner that can typically only be crafted or summoned, like the Wither, End Dragon, Breeze, or Warden)