Monks in the D&D: Adventures in the Forgotten Realms sets incentivize you to play two spells in a turn and have some lifegain synergies, so Oji fits this two categories
It's a fun card with a useful slate of abilities, so get ready
There are enough EDH strategies utilizing this effect to warrant its near $7 value
Elder Gargaroth is above the curve on abilities, below the curve on cost, and can easily slide into nearly any Green deck to be effective while at the same time giving its owner notable combat advantages and free resources in the process
This can do a lot of fancy stuff, including copying the activation of a Fetchland to help ramp you, which is a powerful effect to have in blue
Genesect's Fusion Strike System replenishes the player's hand like crazy and can enable huge damage from the Fusion Strike Meloetta's Melodious Echo or MewVMAX's copy attack