Level Up A5E Monstrous Menagerie: A GM's Step-by-Step Guide
By Modiphius US | Published: 2026-11-02
Category: How-to Guides
Turn the Monstrous Menagerie into your session prep engine. Follow these GM steps to pick monsters, build encounters, and run A5E stat blocks with confidence.
Quick answer
Treat the Monstrous Menagerie as a session-prep toolkit, not a bestiary to read cover to cover. Pick monsters by role, build encounters around their variants and templates, and run A5E stat blocks at the table with the same step order every time.
Why the Menagerie changes prep more than it changes monsters
The book's real value is breadth with structure: nearly 600 monsters, variants, templates, and hordes give you options at every tier, but that volume can slow a GM who flips pages looking for inspiration. Decide on the encounter's job first, then search the book for a monster that does that job.
A5E stat blocks also reward a consistent reading habit. If you learn the block's order once, you can run unfamiliar monsters without pausing mid-turn.
Where the Menagerie is not the right tool
If you need a single recurring villain with a long personal arc, a bespoke stat block built for your campaign will usually serve better than any published monster. The Menagerie is strongest for encounter casts, variants, and hordes, not for replacing your campaign's unique antagonist.
Your GM workflow for using the Monstrous Menagerie
- Define the encounter's job before opening the book: Write one line: what should this fight do to the party? Examples: drain resources, showcase a terrain hazard, or introduce a faction. Then search for monsters that fit that job rather than browsing by name. If you cannot state the job in one line, you are not ready to pick a monster.
- Choose a base monster and one variant or template: Start with a monster whose baseline role matches your job, then apply a single variant or template from the book. One modification keeps the stat block readable at the table and makes the encounter feel distinct. Check that the variant does not duplicate a ability the base monster already has.
- Read the A5E stat block in a fixed order: Before play, scan in this order: defenses, movement, primary attack routine, reactions and legendary actions, then traits. Note any trait that triggers at the start of combat so you do not miss it on turn one. If a trait changes the opening round, write it at the top of your notes.
- Build the encounter around the monster's action economy: Count how many meaningful choices the monster gets per round. A solo monster with one attack and no reactions will feel flat; add a horde or a second creature to give the encounter more decision points. If the monster has no reaction or bonus action option, add an environmental effect or ally.
- Run a dry run of the first round: Before the session, simulate the monster's first turn and the party's likely response. This exposes unclear traits, range issues, or saves you may have misread. If the dry run takes more than five minutes, simplify the monster.
- Track variants and templates in your session notes: Record which base monster, variant, and template you used, plus any adjustments. This lets you reuse the same chassis later without re-reading the whole entry. A one-line template like 'stirge + template X' is enough to rebuild the encounter.
Product facts
- Level Up: Advanced 5th Edition - Monstrous Menagerie: Provides nearly 600 monsters, variants, monster templates, and hordes, from the stirge to the tarrasque, plus new horrors like the khalkos and phase monster. You can fill almost any encounter role without leaving the book, which makes it a practical prep reference rather than a one-off purchase.
Level Up: Advanced 5th Edition - Monstrous Menagerie
