It can only put +1/+1 counters on artifact creatures and it can only put charge counters on non-creature artifacts
Stormscape and Nightscape Familiars are also noteworthy additions for being creatures, which black has an easy time reanimating when they die
Gitaxian Probe + Mishra's Bauble Let's put it this way: A cantrip that you can pay for with life rather than mana, and tells you what your foe's up to, is so fundamentally broken that Gitaxian Probe is banned in Modern and Legacy, and it's also restricted in Vintage, where it's no stranger to top-tier decks
However, the fact that Titan can tutor up literally any MTG land in your deck and isn't limited to basics seems to be the real point of contention, as this allows for all kinds of dangerous combos
Also, my comments are in the context of the formats target demographic and broadest part of the player base