Basic lands, Spike, Tournament Grinder, and cards that have been banned or restricted in any official Magic: the Gathering constructed format (and Commander) except for those banned (rather than restricted) in Vintage are legal. This includes cards which were previously banned, but are no longer banned.
Please note that "banned" and "not legal" do not mean the same thing. A format's rules will define which cards are legal, and a banlist will provide exceptions to those rules. For example, in the hypothetical format "Supplemental-Exclusive Constructed," in which only cards that have been printed in supplemental sets and never in Standard-legal sets are legal, Colossal Dreadmaw is not banned, it is simply not legal.
As a result of this, please note that the only legal silver-bordered cards are Spike, Tournament Grinder and any cards which were banned during the brief period of time the Commander Rules Committee allowed silver-bordered cards but included a preemptive banlist.
In MTG Arena, some cards are banned only in best-of-one games. Those are also legal in this format.