Combat profile
For Minecraft 26.3 / NeoForge, wave base values and supported behavior can be changed per registry entry: see health, damage and base armor and mob abilities. Tier, size and wave scaling still apply.
Behavior
It is immune to fire and lava, climbs, supports invaders, and attacks the Nexus. It picks up usable weapons; bows and crossbows switch it to flaming ranged attacks. With mob griefing enabled, it can ignite nearby flammable blocks every 40 ticks.
Drops
In the current Minecraft 26.3 / NeoForge build, the mob's own loot table drops the items below. Each range is rolled independently. These default pools have no Looting bonus; server datapacks can replace them. A minimum of zero means that item can be absent.
Fire Charge • 0–1
Small Remnants • 25% chance of 1The shared IM death hook independently gives a 25% chance of one Small Remnants, in addition to the item-table drops.
Compare the additional mob drops; this is the mod's own loot, rather than an inherited vanilla mob table.
Vanilla replacement
No vanilla mob converts into an Imp; it appears in waves or through its spawn egg.