He basically pairs a Transformer shield with a grenade that does continuous shock damage, like the Hex or the Stormfront. Each tick of damage done by the grenade counts as a tick of splash damage for the purposes of Means of Destruction. I discovered this myself when messing around with the Echo, a Torgue pistol that only fires sticky rounds, but each round explodes three times (I was lucky enough to get a double penetrating version off of a Loot Tink, so 6 explosions per trigger pull).
I dont like going into Bottomless tree, i feel like it gives almost nothing, since for most part im just throwing granades. Shields of Ret give survi and some dmg.
As to granades i found out this cute little nade mode from Vladof with singularity that lay 6 sticki nades that expode when enemy is near. And this little thing have only 121 dmg, but becouse of 7 explosions it does compared dmg to others that im finding, less and less as times fly but i love the singularity thing that pulls enemy to granade and im yet to find another one with this mode. Im lv40 btw
Please use the real talent tree
The bl3skills.com website is very outdated, many of the skills in that were made months ago, and have changed drastically.