This is long overdue, but better late than never: a d20-to-d10 conversion table.
The conversion table uses the ‘d20 System’ concept of the challenge rating to scale monsters down to Tiny d10 toughness levels, producing creatures of equivalent difficulty to their d20-based counterparts. It’s a flexible tool, and provides a general framework for well-balanced conversions while allowing game masters the freedom to adapt, adjust, or eliminate components to make as simple or complex monsters as needed.
Wolf (Medium animal; 2d8 + 4 HD; Init: +2; SPD: 50ft; AC: 14; Base attack: +1; Attack: Bite (+3 melee; 1d6+1); Special attacks: Trip; Saves: FORT +5, REF +5, WILL +1; Abilities: STR 13, DEX 15, CON 15, INT 2, WIS 12, CHA 6; Skills: Hide +2, Listen +3, Move silently +3, Spot +3, Survival +1; Feats: Track, Weapon Focus; CR1).
Next, the same wolf, adapted to TD10 using the conversion table:
Wolf (T5; 5-6 HP; +1 P [10% chance]; +1 perception; fast speed; abilities: Crushing bite [inflict double damage on a natural 10]; skills: Hide).
As always, this content is likely to change as numbers are balanced and fine-tuned. All the same, this should serve as a functional starting-point for expanding the range of mobs and monsters that your players encounter along their journeys.
All ‘d20 System’ content used in compliance with the terms of the ‘d20 System’ Open Gaming License (OGL) v1.0a.