Team Fortress 2 has a similar explosion sound for when the Engineer's dispenser explodes
The sound can also be found on the sound effects CD where Badspot got the majority of Blockland's sounds and music from
SOUNDS/SFX/WEAPONS/WEAP1000 - Rocket explosion
SOUNDS/SFX/WEAPONS/WEAP1001 - Spear explosion
SOUNDS/SFX/WEAPONS/WEAP1005 - Gun fire