Pick-ups: use the opportunity and avoid the hazard
Use the Melta-bomb’s short delay to bring enemies toward its blast; keep yourself out of Purple Sun’s damaging zones. Pick-ups are on-field opportunities, distinct from the weapons and companions selected as a run develops.
The August official reveal describes these pick-ups around faction-themed light sources and distinguishes the two universes. It does not guarantee that every example is obtainable in the October demo, or give drop rates, exact locations or durations.
Warhammer 40,000: explosives and ammo
Melta-bomb
A powerful thermal blast occurs after a short delay. The official suggested use is to kite a mob toward its radius. That means judging where the group will be when the blast occurs, without an invented throw button, inventory system or countdown in seconds.
Blast Template
It causes a large on-screen explosion described as destroying enemies across the screen. Some enemies resist instant-kill effects, so keep an escape option instead of assuming every dangerous target disappears.
Hellfire Ammo
It temporarily increases damage from all ranged attacks and applies Poisoned to enemies. It is an opportunity to use your existing ranged arsenal; it is not a permanent weapon, nor a guarantee of a particular buff duration.
Age of Sigmar: endless spells
Purple Sun of Shyish
Its manifested damaging zones can hurt the player as well as enemies. Do not follow the effect into a hazard simply because you triggered it. The reveal hints at an undisclosed way to keep it around longer, without providing that method.
Ravenak’s Gnashing Jaws
The jaws tether to the player, bite nearby enemies as you move and apply Burning. The published Burning behaviour speeds up affected enemies, so the extra damage does not remove the need to watch your movement space.
Suffocating Gravetide
Its hit first stuns enemies, then makes them flee temporarily. Use that opening to reposition or retaliate; it does not promise an invulnerability window. Stun itself stops movement, not attacks.