Walshy has put together a video to showcase how plasma grenades in Halo 4 may redefine how they are used, and in his opinion, may be classified as a power weapon.
Walshy gives a brief history lesson on how grenades behaved in the previous Halo titles in comparison to Halo 4. For example, grenades in Halo 1 were used to a great extent to pull powerups to the player and an assortment of other grenade tricks. Grenades lent a lot of strategic options to Halo 1, and allowed players to play out many different scenarios with their use of the weapon.
Players who didn't get an ideal spawn could grenade down the top powerups to themselves, or even use grenades to jump up onto ledges.
Grenades behaved differently throughout the Halo series. In Halo 1, you can see that the trajectory of the second grenade is affected by the explosion of the first grenade. It does not explode until it finally comes to a rest. This applies to both plasma and frag grenades.
In Halo 2, they worked much differently when they came into contact with explosions. Frag grenades explode the instant they come in contact with a plasma explosion. Plasma grenades would bounce around for awhile before they exploded.
In Halo Reach, grenades work inconsistently. They'll either explode instantaneously or carry out their full duration after come into contact with an explosion. Halo 3 does not have this inconsistency, and works similarly to how it does in the Halo 4 video showcasing how the second grenade instantly explodes after bouncing off the first grenade's explosion.
Walshy spends the rest of the video to show how the grenades in Halo 4 can be used in the same way they worked in Halo 3 through a gameplay demonstration. It's well worth the watch if you're keen on discovering how these instantly exploding grenades, or instasplodes, can be used as a valid strategy in multiplayer.
It's Walshy's first video on his own channel, so be sure to hit subscribe.